THE APhA COMPLETE REVIEW FOR PHARMACY, 7th Ed

26. Common Dermatologic Disorders - Shaunta' M. Ray, PharmD, BCPS

26-1. Acne (Acne Vulgaris)

Introduction

Acne is an inflammatory disorder of the pilosebaceous glands that occurs most commonly during the teenage years, at or soon after puberty. It may reappear later or begin in adults who had clear skin in their teens, more commonly in women than in men.

Classification and Clinical Presentation

• Type I (comedonal): A mild form, with primarily noninflammatory lesions (open and closed comedones), relatively few superficial inflammatory lesions, and no scarring

• Type II (papular): A moderate form, with multiple papules on the face and trunk and minimal scarring

• Type III (pustular): An advanced form that can lead to moderate scarring

• Type IV (nodulocystic): The most severe and destructive form, with multiple deep inflammatory lesions or nodules (often called cysts) that lead to extensive scarring

Pathophysiology

• Increased sebum production by androgenic hormones at the onset of puberty

• Obstruction of hair follicle opening because of increasing adherence to and production of epithelial cells, producing closed comedones (whiteheads) that progress ultimately to open comedones (blackheads)

• Increased growth of a primary microorganism on the skin and in the sebaceous ducts, Propionibacterium acnes (P acnes), a gram-positive anaerobic rod that produces enzymes (including lipases)

• Inflammation caused by the enzymatic breakdown of triglycerides into free fatty acids, which causes the influx of polymorphonuclear leukocytes, ultimately resulting in pustule formation

Treatment Principles

• Type I (comedonal): Topical nonprescription medications such as benzoyl peroxide, which is usually the first line of therapy

• Type II (papular): Topical antibiotics, topical retinoids, or both

• Type III (pustular): Oral antibiotics in addition to topical medications

• Type IV (nodulocystic): Isotretinoin

Topical Therapy

Nonprescription agents

Benzoyl peroxide is the most effective over-the-counter (OTC) agent. Benzoyl peroxide products 2.5, 5, and 10% are as follows:

• Clean and Clear Gel

• Clearasil maximum strength vanishing cream

• Clearplex

• Exact Acne Medication

• Fostex

• Neutrogena On the Spot Acne Treatment

• Noxzema antiacne lotion

• Oxy-10 Balance Spot Treatment and Face Wash

• Panoxyl Bar

• Stridex Power Pads

• Zapzyt gel

Mechanism of action

These agents destroy the anaerobic P acnes through the release of oxygen. An exfoliant effect occurs, causing peeling of the outer layers of the skin.

P acnes does not become resistant to benzoyl peroxide; therefore, it can be used concurrently with topical antibiotics to prevent resistance (e.g., using benzoyl peroxide for one course of therapy, alternating with a course of topical antibiotic therapy).

Patient counseling

• Use with caution with sensitive skin.

• Do not allow contact with eyes, lips, or mouth.

• Avoid unnecessary sun exposure and use sunscreen.

Adverse effects

• These agents may cause redness, dryness, burning, itching, peeling, and swelling.

• They may bleach hair or dyed fabrics.

Other products

• Sulfur (1-10%): Products include Bye Bye Blemish—sulfur 10% (keratolytic and antibacterial action)

• Salicylic acid (0.5-2.0%): Products include Clearasil Clearstick, Neutrogena Rapid Defense, Noxzema, and Stridex—irritant effect, keratolytic action, and increase in rate of turnover of epithelial cells

• Resorcinol: Keratolytic action (usually combined with sulfur)

• Combinations such as sulfur and resorcinol: Clearasil and Acnomel

• Medicated soaps and cleansers: Alcohol, acetone, and other degreasing lotions

Topical antimicrobial therapy

Topical antimicrobials are outlined in

Table 26-1.

[Table 26-1. Topical Antimicrobials]

Clindamycin

Mechanism of action

Clindamycin suppresses growth of P acnes. It may directly reduce free fatty acid concentrations on the skin.

Patient counseling

• Contact physician if no improvement is seen within 6 weeks.

• Discontinue medication and contact physician if severe diarrhea or abdominal cramps or pain develop.

Adverse effects

• Contact dermatitis or hypersensitivity

• Dry or scaly skin or peeling

• Rarely, pseudomembranous colitis (severe abdominal cramps, pain, bloating, and severe diarrhea)

Erythromycin

Mechanism of action

Erythromycin suppresses growth of P acnes.

Patient counseling

• Wait at least 1 hour before applying any other topical acne medication.

• Avoid contact with eyes, mouth, nose, and other mucous membranes.

• Although improvement is generally expected within 4 weeks, some patients do not respond for 8-12 weeks.

Adverse effects

• More common: Dry or scaly skin, irritation, and itching

• Less common: Stinging sensation, peeling, and redness

Retinoids

See

Table 26-2 for information about retinoids.

Mechanism of action

• Retinoids are chemically related to vitamin A.

• Retinoids normalize follicular keratinization, heal comedones, decrease sebum production, and decrease inflammatory lesions.

Patient counseling

• Do not use astringents, drying agents, abrasive scrubs, or harsh soaps concurrently, and use mild soap only once or twice daily.

[Table 26-2. Retinoids]

• Apply every other night to adjust to drying effect for the first 2 weeks.

• Apply nightly after 2 weeks.

• Expect that it may take up to 2-3 months for skin to improve.

• Use sunblock on face before sun exposure because of increased sensitivity.

Adverse drug effects

• These agents may irritate skin and cause redness, dryness, and scaling.

• Tazarotene is the most irritating retinoid.

• Adapalene appears to be least irritating and is preferred for sensitive skin.

Azelaic acid 20%

Trade names are Azelex and Finacea.

Mechanism of action

Axelaic acid 20% suppresses growth of P acnes. It improves inflammatory and noninflammatory lesions. It normalizes keratinization, leading to an anticomedonal effect.

Patient counseling

• If sensitivity develops, discontinue use.

• Keep away from mouth, eyes, and mucous membranes.

• Other topical medications must be used at different times during the day.

Adverse drug effects

• Temporary dryness and skin irritation (pruritus and burning) may occur on initiation of therapy.

• Hypopigmentation may occur (caution in dark-skinned individuals).

Systemic Therapy

Antimicrobials

Antimicrobials are useful for type II (papular) acne and type III (pustular) acne.

Dosing

See

Table 26-3 for information about dosage. After 6-8 weeks, dosage may be increased if necessary. If the first antibiotic was ineffective after increasing the dosage, a second antibiotic is prescribed.

After 6 months to 1 year of therapy, the antibiotic dose may be tapered if continued at all.

Mechanism of action

Antimicrobials suppress growth of P acnes in sebaceous ducts. These agents possibly have a direct anticomedonal effect.

Patient counseling, adverse drug effects, and drug interactions

See chapter on anti-infective agents.

Isotretinoin

Isotretinoin is available in 10, 20, and 40 mg capsules. Trade names are Accutane, Amnesteem, Claravis, and Sotret.

Isotretinoin is for patients with severe, nodulocystic, draining acne who have not responded to systemic antibiotic therapy or who have required more than 3 years of systemic antibiotic therapy.

This agent is over 90% effective in producing an acne-free state for years following a 4- to 5-month course of therapy. Originally held in reserve for severe cases of nodulocystic acne, it may also be indicated as first-line treatment for severe acne that results in scarring.

[Table 26-3. Oral Antimicrobials]

iPLEDGE program

The U.S. Food and Drug Administration (FDA) has approved an enhanced risk management program designed to minimize fetal exposure to isotretinoin known as iPLEDGE, which replaced the S.M.A.R.T. (System to Manage Accutane Related Teratogenicity) Program on December 30, 2005. iPLEDGE requires mandatory registration of prescribers, patients, wholesalers, and pharmacies to further the public health goal of eliminating fetal exposure to isotretinoin.

Pharmacies are not able to dispense isotretinoin to people with severe acne who do not enroll in the iPLEDGE program through a physician who is also enrolled. After a pharmacy registers for iPLEDGE at www.ipledgeprogram.com, the "Responsible Site Pharmacist" is sent a follow-up mailing, which contains instructions on how to activate the pharmacy.

The iPLEDGE program requires that all patients meet qualification criteria and monthly program requirements. Before the patient receives his or her isotretinoin prescription each month, the prescriber must counsel the patient and document in the iPLEDGE system that the patient has been counseled about the risks of isotretinoin.

Mechanism of action

Isotretinoin reduces sebum production (up to 90% inhibition). It decreases production of microcomedones, possibly by decreasing cohesiveness of follicular epithelial cells. It can have an anti-inflammatory effect.

Patient counseling

• Isotretinoin should be taken with food and is best absorbed with a fatty meal.

• Patients can take the dose divided twice daily or the entire dose with the evening meal.

• Effects are gradual, and acne may worsen during the first month of therapy; however, improvement usually begins by the sixth week of therapy.

• Use lip balm to treat cheilitis and moisturizers to treat dry skin.

Adverse drug effects

Isotretinoin is teratogenic. It is absolutely contraindicated in pregnancy because it causes significant birth defects. Females of childbearing potential must take measures to avoid pregnancy during the course of isotretinoin therapy.

Females should be tested for pregnancy before initiation of therapy and told to use two methods of contraception for at least 1 month prior to initiation of therapy and for 1 month after discontinuation of therapy.

Side effects and toxicity

• Most common (90-100%):

• Cheilitis (chapped lips)

• Dry mouth

• Dry skin

• Pruritus

• Common (30-40%):

• Dry nose, leading to nasal crusting and epistaxis

• Dry eyes, leading to conjunctivitis and problems with contact lenses

• Muscular soreness or stiffness

• Less common (10-25%):

• Headaches

• Hyperlipidemia (primarily elevation of triglycerides, which may lead to attack of pancreatitis)

• Rare (less than 5%):

• Decreased night vision

• Thinning of hair

• Easily injured skin

• Peeling of palms and soles

• Skin rash and skin infections

• Very rare (< 1%):

• Acute depression (very rare, but reversible if detected early)

• Pseudotumor cerebri (benign intracranial hypertension with visual disturbances)

• Treatment of most common side effects:

• Cheilitis: Frequent use of lip balm

• Dry skin: Skin lubrication with moisturizers

• Nosebleeds: Lubrication of the nostrils with petrolatum

• Muscular soreness or stiffness: Use of mild OTC analgesic and anti-inflammatory agents

Monitoring parameters

• Lipid panel

• Liver function tests (elevations common during initiation of therapy; usually return to normal during treatment).

• Complete blood counts

• Pregnancy testing for women prior to use of drug

Dosing

The dosage is 1 mg/kg once or twice daily with food; however, the patient may start out with 0.5 mg/kg/d for the first month before increasing. The drug is best absorbed with a fatty meal.

The goal is a total dose of 120-150 mg/kg over 4-5 months. Longer courses of 6-8 months may be required.

Other aspects

Approximately 20% of patients relapse within 1 year, and up to 40% relapse within 3 years after discontinuation of therapy. Repeat therapy for 4-6 months is acceptable and effective.

Oral corticosteroids

Oral corticosteroids are commonly known as prom pills. These agents can temporarily suppress acne with a 7- to 10-day course of prednisone 20 mg daily. They are rapidly effective when a brief course is necessary to cause prompt improvement (e.g., important social event such as wedding, prom, and so forth).

Systemic corticosteroids used continuously may actually cause or worsen acne. Topical corticosteroids have no value in the treatment of acne, and the high-potency topical corticosteroids will aggravate acne and should never be used on the faces of acne patients.

26-2. Fungal Skin Infections

Introduction

Tinea are skin infections known as dermatomycoses caused by the fungi Trichophyton, Microsporum, and Epidermophyton.

Classification

• Tinea pedis (athlete's foot)

• Tinea capitis (ringworm of the scalp)

• Tinea cruris (jock itch)

• Tinea corporis (ringworm of the skin)

• Tinea unguium (onychomycosis; fungal infection of toenails and fingernails)

Pathophysiology

The fungi invade dead cells of the stratum corneum of skin, hair, and nails, digesting keratin. Unlike Candida, they cannot exist on unkeratinized mucous membranes.

This condition is more common in immuno-suppressed patients.

Treatment Principles and Goals

• Tinea pedis: Self-treat topically initially; if ineffective, add orals.

• Tinea capitis: Use oral systemic therapy.

• Tinea cruris: Self-treat topically initially; if ineffective, add orals.

• Tinea corporis: Self-treat topically initially; if ineffective, add orals.

• Tinea unguium: Use oral systemic therapy.

Drug Therapy

OTC treatment

• Terbinafine 1% (Lamisil AT) cream, gel, and spray (most effective OTC antifungal agent)

• Miconazole 2% (Micatin, Cruex Spraypowder)

• Clotrimazole 1% (Lotrimin AF lotion, solution, and cream; Desenex AF)

• Tolnaftate 1% (Tinactin, Blis-To-Sol, Ting)

• Undecylenic acid 10-25% (Desenex)

Prescription treatment

See

Table 26-4 for a description of prescription drugs.

Topicals

Newer antifungals are initially applied only once daily, and recurrences can be prevented by once- or twice-weekly applications.

Systemic therapy

Occasionally, topical therapy is not effective for tinea pedis, tinea cruris, and tinea corporis, and systemic antifungal therapy is required. Systemic therapy is also required for tinea capitis (ringworm of the scalp) and tinea unguium (fungal infection of the toenails and fingernails). Medications are as follows:

• Griseofulvin

• Ketoconazole

• Fluconazole

• Itraconazole

• Terbinafine

See chapter on anti-infective agents for discussion of systemic antifungals.

[Table 26-4. Prescription Topical Antifungals]

26-3. Hair Loss (Alopecia)

Introduction

Male pattern baldness (androgenic alopecia) is the gradual and progressive loss of hair in males as they age.

Clinical Presentation

• Onset and progression vary greatly.

• A distinct pattern of progressive hair loss develops in the frontotemporal areas and crown with sparing of the occiput.

• Hair loss is limited to the scalp.

• Miniaturization of hair is seen, where normal thick terminal hairs are converted to very fine vellus hairs.

Pathophysiology

Alopecia is primarily due to two factors:

• Heredity (genetic)

• Testosterone

Testoterone, which promotes growth of hair in the beard, axillae, pubis, and other parts of the body, does not promote the growth of scalp hair. It actually contributes to premature loss because it is converted by the enzyme 5-α-reductase to dihydrotestosterone, which binds preferentially to receptors in the hair follicles on the scalp and causes them to produce progressively thinner hair until the follicles eventually cease activity altogether.

Treatment Principles and Goals

Although there is no cure for androgenic alopecia, two drugs are available for its treatment:

• Minoxidil (Rogaine, available OTC)

• Finasteride (Propecia, by prescription only)

In alopecia's early stages, topical minoxidil or oral finasteride may reverse the gradually decreasing diameter of the hair shaft.

Any hair growth stimulation is temporary and lasts only as long as therapy continues. If therapy is discontinued, new hair growth is lost within 1 year.

Early hair loss occurring recently in younger men is more likely to respond than later hair loss at an older age or when hair loss is not recent.

Alopecia of the crown in males responds better than does hair loss in the frontotemporal area.

Drug Therapy

Minoxidil

OTC trade names are Rogaine 2% and Rogaine Extra Strength 5%.

Mechanism of action

Minoxidil probably increases cutaneous blood flow directly to hair follicles due to vasodilation. It possibly stimulates resting hair follicles (telogen phase) into active growth (anagen phase). It possibly stimulates hair follicle cells.

Patient counseling

• Apply 1 mL twice daily (approximately one 60 mL bottle each month).

• Minoxidil may be applied without shampooing hair.

• Use at least 4 hours before bedtime to avoid oil on pillows and bed linens.

• The drug is absorbed over a 4-hour period, so do not swim, shampoo, or walk in rain for 4 hours.

• Wash hands immediately after application to prevent unwanted absorption.

• Do not inhale mist because systemic absorption is possible.

• Do not use on infected, irritated, inflamed, or sunburned skin.

• Discontinue use immediately and contact physician if chest pain, increased heart rate, faintness or dizziness, or swollen hands or feet occur.

• Women should avoid 5% strength (which has no better results than 2%); they have greater incidence of increased growth of facial hair with the 5% solution.

• Generally, treatment takes 4-6 months before any benefit occurs.

• No effects within 8 months for females and 12 months for males indicate therapeutic failure, and treatment should be discontinued.

• Patients must continue using minoxidil to maintain new hair growth.

Adverse drug effects

• Scalp dermatitis is common, producing dryness, pruritus, and flaking or scaling.

• Hypertrichosis (excessive hair growth) can occur on areas other than scalp (chest, forearms, ear rim, back, face, arms, and so forth).

• Some women report unwanted facial hair growth when minoxidil is applied to scalp, primarily with the 5% solution.

• Use may rarely produce systemic side effects (chest pain, increased heart rate, and faintness or dizziness).

• Use is contraindicated in patients less than age 18.

• Use is contraindicated in women who are pregnant or breastfeeding.

Finasteride

The trade name of finasteride is Propecia 1 mg. It was originally approved in 1992 for the treatment of enlarged prostate glands (benign prostatic hypertrophy) in a 5 mg dose (Proscar). A 1 mg daily dose is approved for males only as prescription treatment for androgenic alopecia.

Over a 2-year period, it may halt the progressive hair loss of androgenic alopecia.

Mechanism of action

Finasteride inhibits the enzyme 5-α-reductase, which is responsible for the conversion of testosterone to the more powerful dihydrotestosterone—the main androgen responsible for androgenic hair loss.

Patient counseling

• Take with or without food.

• Take for at least 3 months to see if the drug is effective.

• Improvement lasts only as long as treatment continues (new hair will be lost within 1 year of stopping treatment).

Adverse drug effects

• Gynecomastia (breast enlargement and tenderness) has been reported from 2 weeks to 2 years following initial therapy, but it is usually reversible when therapy is discontinued.

• Hypersensitivity (skin rash, swelling of lips)

• Decreased libido, erectile dysfunction, and ejaculatory dysfunction occur, which are reversible when the drug is discontinued.

• Use is contraindicated in females of childbearing age, because of abnormalities of the external genitalia in male fetuses; it is also not effective in postmenopausal females.

26-4. Dry Skin

Introduction

This condition refers to lack of moisture or sebum in the stratum corneum. It most commonly occurs in the winter (also known as winter rash). It is more commonly present in older adults.

Clinical Presentation

• Flaking and scaling

• Xerosis and roughness

• Pruritus

• Loss of skin elasticity

Pathophysiology

Dry skin is due to inadequate moisture retention in the stratum corneum, which is caused by the following factors:

• Decreased sebum production and decreasing moisture-binding capacity of skin in elderly patients

• Low humidity, which causes the skin to lose water and become dry and hardened

• Overexposure to sunlight

• Excessive cleansing and bathing, which removes lipids and other skin components

• Chronic skin diseases that impair moisture retention of skin (psoriasis, scleroderma, ichthyosis, contact dermatitis)

Treatment Principles and Goals

The goal of treatment is to increase the moisture level of the stratum corneum by increasing cell hydration and binding capacity, which improves skin permeability and restores elasticity.

Drug Therapy

Emollients and moisturizing agents

Emollients and moisturizing agents include petrolatum and mineral oil (Lubriderm Bath and Shower Oil). They increase the relative moisture content of the stratum corneum and produce a general soothing effect by reducing frictional heat and perspiration.

Humectants

Humectants include glycerin (Corn Husker's Lotion), propylene glycol, and phospholipids. They are hygroscopic agents that increase hydration of the stratum corneum.

Keratin-softening agents

Keratin softening agents include the following:

• Urea (10-30%) (Aquacare and Carmol)

• Improves the skin's moisture-binding capacity

• Provides keratolytic effect at higher concentrations

• May cause irritation and burning

• Lactic acid (2-5%) (LactiCare)

• Increases skin hydration by controlling the rate of keratinization

• Is markedly hygroscopic

• Allantoin (Alphosyl, Psorex, Tegrin)

• Relieves dry skin by disrupting keratin structure (less effective than urea)

• Desensitizes many skin-sensitizing drugs as a protectant

Antipruritic agents

Antipruritic agents include the following:

• Camphor and menthol, which provide a cooling sensation

• Local anesthetics (e.g., benzocaine, pramoxine)

• Systemic antihistamines (H1-receptor antagonists), which have limited effectiveness

• Colloidal oatmeal (Aveeno)

Caution: Colloidal oatmeal can cause an extremely slippery bathtub.

Hydrocortisone

Hydrocortisone reduces the inflammatory response that accompanies dry skin conditions. Although it does not directly increase skin hydration, it does prevent itching associated with dry skin and inhibits dehydration.

Ointment is better than cream for dry skin. Patients should be counseled as follows.

• Use sparingly.

• Do not use more than 5-7 days for dry skin pruritus.

Astringents

Astringents include aluminum acetate 0.1-0.5% (Burow's solution) and hamamelis water (witch hazel).

Protectants

Zinc oxide is a protectant.

Nondrug Recommendations and Therapy

• Bathe less frequently.

• Reduce use of soap to a minimum and use only where necessary.

• Lubricate skin immediately after bathing (i.e., apply bath oil after bathing and before drying).

• Use extrafatted soaps such as Basis.

Combination products to treat dry skin

• Alpha Keri Moisture Rich Cleansing Bar: Mineral oil, lanolin oil, and glycerin

• Aveeno Bath Treatment Moisturizing Formula: Colloidal oatmeal and mineral oil

• Jergens Advanced Therapy Ultra Healing Lotion: Dimethicone, lanolin, cetyl alcohol, isopropyl myristate, and glycerin

• Keri Original Dry Skin Lotion: Mineral oil, lanolin oil, glyceryl stearate, and propylene glycol

• Moisturel Cream and Lotion: Petrolatum, dimethicone, cetyl alcohol, and glycerin

• Neutrogena Body Oil: Isopropyl myristate and sesame oil

• Pacquin Plus Dry Skin Hand and Body Cream: Lanolin anhydrous, cetyl alcohol, and glycerin

• Vaseline Dermatology Formula Lotion: White petrolatum, mineral oil, dimethicone, glyceryl stearate, cetyl alcohol, and glycerin

26-5. Dermatitis

Introduction

Dermatitis is a nonspecific term describing a variety of inflammatory dermatologic conditions characterized by erythema. It is a general term describing any eczematous rash of unknown etiology that cannot be classified among the major endogenous dermatoses. Eczema and dermatitis are often used interchangeably.

Types and Classification

Several of the major classifications or types of dermatitis are

• Atopic dermatitis (atopic eczema)

• Chronic dermatitis (hand dermatitis)

• Contact dermatitis (irritant and allergic)

Clinical Presentation

Atopic dermatitis (atopic eczema)

Atopic dermatitis occurs primarily in infants and children. It may disappear before adulthood. The cause is unknown but is possibly genetic.

Atopic dermatitis is usually seen on the face, knees, elbows, and neck. It is frequently seen with asthma, allergic rhinitis, and urticaria. Exacerbating factors include soaps, detergents, chemicals, temperature changes, molds, and allergens.

Chronic dermatitis (hand dermatitis or hand eczema)

Chronic dermatitis is a stubborn itchy rash referred to as eczema that occurs in certain persons with sensitive or irritable skin. The skin is very dry and easily irritated by overuse of soaps or detergents and by rough woolen clothing.

The condition is exacerbated by very hot or very cold weather. It is probably genetically determined. No permanent cure exists.

The condition usually can be controlled by enhancing skin hydration with emollients and moisturizers and by using hydrocortisone cream to relieve itching.

Contact dermatitis

Irritant contact dermatitis (chemical contact dermatitis)

The condition is caused by exposure to irritating substances producing mechanical or chemical trauma. Examples include soap, solvents, paints, abrasive cleansers, cosmetics, lubricants, antiseptics, cacti, rose hips, thorns, peppers, and tobacco.

Irritant contact dermatitis is not a sensitization, but direct toxicity to skin tissue.

Allergic contact dermatitis

The condition is a process of sensitization with reaction on elicitation. Over 50% of all dermatitis is allergic contact dermatitis.

Examples of reactive elements include benzocaine, zinc pyrithione (ZPT), neomycin, sodium bisulfite, perfumes, many cosmetics, skin lubricants, antiseptic creams, rubber and epoxy glues, poison ivy and oak, and many other common substances.

Treatment Principles and Goals

Treat dermatitis by applying a corticosteroid, according to the following principles:

• Ointments and creams are more lubricating than solutions, lotions, or gels.

• Ointments should be recommended if skin is dry.

• Lotions or gels should be recommended for a weeping, eczematous dermatitis.

• Lotions, solutions, and gels are also easier to use in hairy areas of the body.

• Apply small amounts of corticosteroid cream or ointment, and massage in gently but thoroughly.

• Apply the moderate- and high-strength cortisones only once daily.

• Improvement should begin within 1 week.

• Avoid excess soap, and keep skin lubricated with moisturizers.

• Treat itching with camphor, menthol, phenol, or local anesthetics.

• Occasionally with severe cases (less than 5%), patients may have to use systemic corticosteroids for 1-2 weeks.

Drug Therapy

Topical corticosteroids

See

Table 26-5 for information about topical corticosteroids.

Adverse effects

• Striae may result in skin folds.

• Thinning of epidermis occurs where subcutaneous vessels become visible.

• The more potent types can cause or aggravate acne or rosacea on the face.

• Percutaneous absorption can lead to systemic effects (see Chapter 14 on endocrine drugs for complete list of systemic adverse effects).

• Hyperglycemia

• Glycosuria

• Hypothalamic-pituitary-adrenal axis suppression, which could pose a threat in case of surgery, systemic illness, or trauma or injury

• Percutaneous absorption leads to systemic effects most likely with the following:

• The higher potency types of agents

• Inflamed skin (also in infants and children)

• Long-term use or use over a large area of the skin

• Caution: Occlusion markedly increases absorption of topical corticosteroids and should therefore be used cautiously in limited areas and reserved for severe, resistant lesions.

Topical antipruritics

Topical antipruritics include the following:

• Local anesthetics (benzocaine up to 20%, pramoxine 1%)

• Benzyl alcohol

• Colloidal oatmeal (Aveeno)

• Others (camphor, menthol, phenol)

Emollients

• Petrolatum

• Lanolin

• Mineral oil

[Table 26-5. Typical Pharmaceutical Ingredients]

Topical immunomodulators

Topical immunomodulators are approved for atopic dermatitis. They inhibit activation of T-cells and release of certain inflammatory mediators (cytokines).

The medication is applied bid, with onset in 1-3 weeks. Side effects include stinging, burning, pruritus, and rare flu-like symptoms. Patients should be cautioned to use sunscreen.

Immunomodulator products are as follows:

• Tacrolimus (Protopic) 0.03% and 0.1% ointment

• Pimecrolimus (Elidel) 1% cream

Oral corticosteroids

Corticosteroids are the only systemic anti-inflammatory agents that are effective.

Oral antihistamines

Oral antihistamines have very limited effectiveness but are possibly antipruritic.

26-6. Poison Ivy, Poison Oak, and Poison Sumac Allergy (Rhus Dermatitis)

Introduction

Allergic reaction occurs to sap (urushiol) of some plants of the genus Rhus (poison ivy, poison oak, poison sumac). Rhus dermatitis is the most common form of allergic contact dermatitis.

Direct contact with leaves, roots, or branches is not required to get a rash. Sap can reach skin indirectly from clothing, a pet, or burning (volatilization).

Rhus allergy is acquired; individuals are not born with it. Most persons are sensitized to Rhus because it is such a common plant; however, some people are never allergic to it. No effective way exists to desensitize a person with an allergy to Rhus plants.

Types and Classification

• Mild: Localized patches of pruritus and erythema develop, followed by appearance of vesicles and papules on the upper or lower extremities.

• Moderate: Extensive pruritus and irritation develop, with severe vesicles and appearance of bullae and edematous swelling.

• Severe: Extreme pruritus, irritation, and severe vesicle and bullae formation appear. Extensive involvement occurs, widespread over the body, face, or both. Extensive edema of the extremities or face develops. Eye, genitalia, or mucous membrane are involved.

Clinical Presentation

• Rhus dermatitis is not contagious.

• Fluid in blisters does not spread rash.

• Rash appears after a latent period that varies from 4 hours to 10 days, depending on an individual's sensitivity and the amount of plant contact.

• When more rash appears after treatment has begun, these are areas with a longer latent period.

• Symptoms may last from 5 to 21 days following initial rash.

• Secondary infections can occur if scratching excoriates the skin and the abrasions become infected.

Treatment Principles and Goals

Rhus dermatitis is self-limited. Mild cases will clear without treatment within 7-14 days.

The goal of treatment is to prevent itching and excessive scratching and possible secondary skin infections.

Treatment options

• Mild cases: Use topical antipruritics, such as calamine, camphor, menthol, phenol, or local anesthetics to prevent itching and topical hydrocortisone cream or ointment.

• Moderate cases: Use topical high-potency corticosteroids for small areas.

• Severe cases: Use systemic corticosteroids daily up to 2 weeks. Severe rash needs systemic corticosteroids to ease the misery and disability. Systemic corticosteroids are usually needed during early severe stages because remedies applied to skin may not penetrate deeply enough.

Therapy

OTC topical therapy

Astringents and protectants

Compresses, soaks, or wet dressings will dry the oozing, reduce the weeping, aid in removal of crusts, and soothe the skin. They include

• Aluminum acetate solution 1:40 ratio (Burow's solution)

• Aluminum sulfate (Domeboro powder)

• Calamine lotion

• Other products such as aluminum hydroxide gel, kaolin, zinc acetate, zinc carbonate, and zinc oxide

Local anesthetics

These products may contain benzocaine up to 20%, pramoxine 1%, and benzyl alcohol. They include

• Caladryl lotion: Calamine and pramoxine 1%

• Ruli calamine spray: Calamine, benzocaine, and camphor

• Ivarest 8-Hour Medicated Cream: Calamine and diphenhydramine 2%

• Ivy Dry Cream: Benzyl alcohol, camphor, menthol, and zinc acetate

Other products

Other products include

• Hydrocortisone 1% products

• Colloidal oatmeal (Aveeno) for temporary skin protection from exposures

• Cool compresses

Prescription topical therapy

Use topical medium- to high-potency corticosteroids (see discussion on allergic contact dermatitis in Section 26-5).

Prescription systemic corticosteroid therapy

Use of systemic corticosteroids is the only therapy that will actually reduce the severity and duration of the allergic response. See the discussion on allergic contact dermatitis in Section 26-5 and the discussion on endocrine disorders in Chapter 14 for complete details.

Effects of oral corticosteroids are dramatic (patients can take up to 40-100 mg prednisone for 2 or 3 weeks if necessary); however, many patients clear up quickly with a corticosteroid dosepak (e.g., Decadron or Medrol). Extremely severe cases or large-scale rash may require parenteral dose of corticosteroid (100 mg prednisone equivalent).

Other recommendations

Prevention

• Avoidance: Identify the plants—"leaves of three, let it be."

• Removal: Washing with soap and water within 15 minutes of exposure may reduce the extent and duration of dermatitis.

• Use of bentoquatam 5% solution: Marketed under the trade name Ivy Block, this lotion is an organoclay. It is the only barrier product approved by the FDA. Patient instructions are to apply the lotion 15 minutes before possible plant contact and reapply every 4 hours.

26-7. Scaly Dermatoses

Introduction

There are three common forms of scaly dermatoses: dandruff, seborrhea, and psoriasis.

Dandruff

Dandruff is a chronic, noninflammatory scalp condition resulting in excessive scaling of the scalp epidermis. It is a common condition affecting 20% of the population. Though not a serious disorder, dandruff can be cosmetically unsightly.

Clinical presentation

Scaling and pruritus occur, causing white flakes to accumulate on the scalp.

Pathophysiology

Increased epidermal cell turnover rate of approximately twice normal (time reduced from 25-30 days to 13-15 days) prevents complete keratinization of desquamated cells due to unknown processes. Dandruff may be related to increased Pityrosporum ovale (P ovale), a fungal scalp organism.

Treatment

Routine shampooing with mild hypoallergenic shampoo is essential.

Cytostatic agents

Cytostatic agents suppress cell turnover. The goal is to reduce the epidermal rate of turnover of scalp cells. Agents and their mechanisms of action are as follows:

• ZPT (0.3-2%): Products include Denorex, Head and Shoulders, Sebulon, X-Seb, and Zincon. ZPT has antifungal effect and reduces cell turnover rate.

• Selenium sulfide 1%: Products include Head and Shoulders Intensive Treatment, Selsun Blue 1%, and Selsun 2.5%. Selenium sulfide reduces the cell rate turnover and inhibits growth of P ovale.

• Coal tar: Products include Balnetar, Denorex, DHS Tar, Ionil T, Neutrogen T, Pentrax, and Polytar. Coal tar reduces the number and size of epidermal cells.

Patient should be counseled that contact time with cytostatic agents is very important for effectiveness. Advise patients to rub shampoo in well and leave it in up to 5 minutes before rinsing it out.

Keratolytic agents

Keratolytic agents include the following:

• Salicylic acid (1.8-3%): Products include Ionil, Neutrogena, Scalpicin, and Sebucare. Salicylic acid can lower the pH of tissues, thereby increasing the water concentration of epidermal cells, which softens and destroys the stratum corneum. It causes the upper skin layer to become inflamed and soft, followed by desquamation. This keratolytic action removes the scales of dandruff.

• Sulfur (2-5%): Products include Sulfoam, Sulray, and Exsel. Sulfur possibly exerts an antifungal effect. Sulfur is usually found in combinations with salicylic acid.

• Combination of sulfur and salicylic acid: Products include Meted and Sebulex.

Antifungals

Antifungals include the following:

• Ketoconazole (1%) shampoo (Nizoral AD)

• Ciclopirox 1% shampoo (Loprox)

Ciclopirox is active against P ovale. Patients should be counseled to use it twice weekly or every 3 or 4 days. Stress adequate contact time for a minimum of 3 minutes. Adverse effects include itching, stinging, or irritation.

Seborrhea (Seborrheic Dermatitis)

Seborrhea is a chronic inflammatory skin disease in areas of greatest sebaceous gland activity—on the scalp and other hairy areas such as the face, trunk, armpits, and groin. Seborrhea is not contagious. It persists for life, but it can be controlled.

Clinical presentation

• Scaling rash accompanied by pruritus

• Yellowish, greasy scales unlike the dry scales of dandruff

• Inflammation, often accompanied by erythema

• Fluctuation in severity, characterized by exacerbations and remissions

• Most common on the face, eyebrows, and eyelashes, but not on the extremities

• Aggravated and worsened by nervous stress and poor health

Pathophysiology

• Accelerated cell turnover rate is approximately three times normal rate, probably as few as 9-10 days.

• Seborrhea has a higher cell turnover rate than dandruff, but less than psoriasis.

• P ovale may be causative, but this is not universally accepted.

Treatment

Treatment is similar to that for dandruff, but seborrhea is more difficult to treat. Overuse of selenium can make the scalp oily and actually exacerbate seborrhea.

Topical corticosteroids (e.g., Cortaid) are used to control itching and inflammation (up to 7 days) Add the topical antifungal ketoconazole 1% shampoo (Nizoral AD) or ciclopirox 1% shampoo (Loprox). The combination is active against P ovale. Patients should be counseled to use it twice weekly, every 3 or 4 days. Stress adequate contact time; leave it in for at least 3 minutes. Adverse effects include itching, stinging, or irritation.

"Cradle cap" (infantile seborrheic dermatitis)

Cradle cap is seborrhea of the scalp in newborns or infants. It is most common in the first few months of life. It is usually on top of head and may be due to poor washing.

Cradle cap is probably not related to fungal infection. It is treated as follows:

• Massage with oils.

• Use nonmedicated shampoos.

• Use milder keratolytics (Meted and Sebulex) two or three times per week.

Psoriasis

Psoriasis is a chronic inflammatory papulosquamous erythematous skin disease. It is marked by the presence of silvery scales with sharply delineated edges. Lesions are usually localized, but can gradually grow to cover large areas.

Psoriasis can have significant physiological and psychological effects. It affects 1-3% of the population, 98% Caucasian.

Classification

• Type I: Characterized by early age of onset, family history, and increased frequency of human lymphocyte antigen

• Type II: Characterized by development later in life and no family history

Pathophysiology

A hyperproliferative skin condition results from skin cell turnover rate of approximately 10-20 times normal. Skin cells of psoriatic plaque reach the outermost layer in 3-4 days.

A genetic predisposition contributes, as well as exposure of the skin to trauma or triggering factors such as stressful incidents.

Clinical presentation

• Plaque is most common and is known as psoriasis vulgaris.

• Plaque is known also as scales—silvery on top and pink to red beneath.

• Plaque may be found anywhere on the body, but more likely on scalp, sacral area, and extensor surfaces of knees and elbows (less common on face).

• Borders of plaque are sharp with inflammation surrounding the plaque.

• Psoriasis is a chronic condition and varies from mild forms of the disease to very severe, with such extensive coverage that it hinders social and work life.

• It is marked by spontaneous exacerbations and remissions.

Treatment

Topicals

Topical treatments are as follows:

• Topical corticosteroids

• Coal tar (contained in Denorex, DHS, Ionil T, MG217, Neutrogena T, Pantene Pro-V, Polytar, Tegrin, and X-Seb T Plus)

• Keratolytics (salicylic acid, sulfur)

• Combinations of salicylic acid, sulfur, and coal tar (Sebutone)

• Retinoids (tretinoin, adapalene, tazarotene, alitretinoin)

• Anthralin (Anthraforte, Anthranol, Dritho-Scalp)

• Calcipotriene (Dovonex ointment, cream, and solution—a vitamin D3 analog)

Caution: If used in conjugation with PUVA (psoralens with ultraviolet-A) therapy, calcipotriene should be applied after light treatment, because PUVA inactivates this product.

Systemic treatment

Systemic treatment may involve the following:

• Oral corticosteroids

• Antimetabolites, such as methotrexate and cyclosporine

• Psoralens (combined with ultraviolet light therapy)

• Immunosuppressants, such as alefacept (Amevive) and etanercept (Enbrel)

• Retinoids, such as acitretin (Soriatane)

Vitamin A analogs are reserved for severe and extensive psoriasis. Their effectiveness approaches that of methotrexate or cyclosporine when combined with ultraviolet light therapy. Adverse effects include dry lips, skin, nail changes, dry eyes, hair loss, hyperlipidemia, pancreatitis, hepatotoxicity, myalgias, and arthralgias. Such drugs are teratogenic. The above listed AE are primarily with systemic therapy; however, topical therapy may also be teratogenic.

Other therapy

Ultraviolet light therapy is also used, often following coal tar applications or concurrent with oral psoralens.

26-8. Pediculosis

Introduction

Head lice is the primary or most common form of pediculosis. Lice are very common, especially in schoolchildren. They are transmitted by direct contact with the head of an infected individual or through fomites (inanimate objects capable of transmitting disease, such as shared combs, brushes, or headwear). Lice are most common in August and September, after long holidays or summer camps.

Body lice are a less common form that usually occur in individuals who do not change clothing often (e.g., the homeless).

Pubic lice (crab lice) are transferred through sexual contact and are found primarily in pubic areas, but they can also affect armpits.

Classification

There are three types of human pediculosis:

• Head lice: Pediculus humanus capitis

• Body lice: Pediculus humanus corporis (same species as head lice)

• Pubic lice: Pthirus pubis (different species)

Clinical Presentation

• Pruritus is the most common symptom.

• Because lice are often symptomatic, diagnosis is made visually by seeing live lice.

• The flat, gray-brown adult lice are difficult to locate or visualize; the nits (larvae) firmly attached to hair shafts may be more visible.

Drug Therapy

Synergized pyrethrins (0.17-0.33%)

This drug is a natural chemical derived from chrysanthemums that is synergized by addition of 2-4% piperonyl butoxide (petroleum derivative). Trade names include A-200, End-Lice, Lice-Enz, Pronto, R&C shampoo, and Rid.

Mechanism of action

Transmission of nerve cell impulses is blocked in lice, causing paralysis.

Patient counseling

• Wash and dry hair and apply for 10 minutes.

• Use a lice-nit combination to remove dead lice and nits following rinsing.

• Treat all family members.

• Avoid contact with the eyes, mouth, and nose

• Do not use on irritated or inflamed scalp.

• Repeat treatment in 1 week to 10 days.

Adverse drug effects

Adverse effects include irritation, erythema, and itching.

Permethrin 1% and 5%

Permethrin is a synthetic chemical derivative of pyrethrin. Permethrin 1% is available under the trade name Nit Cream Rinse. Permethrin 5%, at prescription-only strength, is available under the trade names Acticin and Elimite Cream.

The 1% OTC-strength treatment is approved for head lice only; however, it is effective against pubic lice. The 5% prescription-strength treatment is approved for scabies l (mites) infestation.

Patients prefer these treatments because of single-application effectiveness.

Mechanism of action

• Transmission of nerve cell impulses is blocked in lice, causing paralysis.

Patient information

• Apply to washed hair and scalp.

• Leave on hair for 10 minutes, and then rinse.

• After rinsing, comb hair with lice comb to remove lice and nits.

• This is a one-time treatment; do not repeat for 10 days.

• All family members should be treated.

Adverse effects

Scalp irritation, pruritus, and stinging may occur. This medication is contraindicated in patients who are allergic to chrysanthemums and in children under age 2.

Lindane (Kwell shampoo, cream, and lotion; prescription only)

Formerly named gamma benzene hexachloride, lindane is effective against head lice and public lice and against scabies (caused by Sarcoptes scabiei).

Adverse effects

Lindane is absorbed significantly through the skin and has been reported to have significant neurotoxic effects, especially in infants and children. Central nervous system effects reported include convulsions, dizziness, lack of coordination, restlessness, and irritability. Other effects include rapid heartbeat, muscle cramps, and vomiting.

The OTC medications are considered much safer, especially in children.

Nondrug recommendations

• Change clothing daily.

• Treat infested clothes, and shower daily.

• All household contacts should be inspected and treated if necessary.

• All bed linens and clothes should be dry cleaned or washed in the hot water cycle and dried on the heated-air cycle for at least 20 minutes.

• Wash hairbrushes, combs, and toys in hot water for at least 10 minutes.

• Treat surrounding environment (bedding, pillows, carpets, draperies, and furniture) with A-200 Control Spray or Rid Control Spray.

26-9. Warts

Introduction

Warts (verrucae) are harmless skin growths resulting from an infectious disease caused by the human papillomavirus.

Classification

• Common warts (verruca vulgaris) are on fingers, hands, and knees.

• Common flat warts (verruca plana) are on face, hands, and legs.

• Plantar warts (verruca plantaris) are on the soles of the feet.

• Anogenital warts (verruca genitalia) are on the anogenital area.

Clinical Presentation

• Warts are contagious, and may spread on the body.

• Warts are more common in children and immunocompromised patients.

• Warts on the face or hands protrude.

• Warts occurring on pressure areas such as the bottom of the feet (plantar warts) grow inward from the pressure of standing and walking, are often painful, and may be confused with corns.

Treatment Principles and Goals

Warts can be eliminated by the following:

• Direct application of caustics, such as salicylic acid, formalin, lactic acid, trichloroacetic acid, and podophyllin

• Freezing (cryotherapy) with liquid nitrogen or with dimethyl ether and propane

• Surgery

OTC drug therapy

Salicylic acid

Patients should be counseled as follows:

• Use topical salicylic acid preparations on a daily basis until the wart is removed.

• Because warts are contagious, use special care in washing hands before and after treatment, and use a separate towel for drying other parts of the body.

• Do not use salicylic acid on irritated, broken, or infected skin.

• If the wart remains after 12 weeks of continuous treatment, see a dermatologist or podiatrist.

Salicylic acid products are contraindicated in patients with diabetes and other patients with poor circulation because reduced sensation in the foot delays awareness of skin breakdown, allowing possible development of infection that can lead to sepsis. Diabetic patients should see a physician or podiatrist for removal of warts.

OTC salicylic acid products are as follows:

• Salicylic acid 17% in flexible collodion vehicle: Compound W gel and liquid, Dr. Scholl's Fast Acting Liquid, Duofilm, Wart-Off, and Off-Ezy Wart Remover Kit

• Salicylic acid 40% embedded in pads or discs: Compound W One Step Pads, Dr. Scholl's Clear Away, DuoFilm, and Dr. Scholl's Clear Away Wart Remover Patch

Cryotherapy

Dimethyl ether and propane is FDA approved for OTC removal of common warts and plantar warts.

Cryotherapy irritation leads the host to produce an immune response against the causative virus (similar to liquid nitrogen, which can be administered only by a primary care provider). As a result of freezing, a blister will form under the wart. After about 10 days, the frozen skin and wart fall off, revealing newly formed skin underneath.

Cryotherapy products are as follows:

• Dimethyl ether and propane: Dr. Scholl's Freeze Away Wart Remover and Wartner Wart Removal System are approved for removal of common warts.

• Dimethyl ether, propane, and isobutane: Compound W Freeze Off is approved for removal of common warts and plantar warts.

Patient instructions are as follows:

• Place the applicator in the spray can, which becomes very cold (-55°C)

• After the applicator is saturated, hold it on the wart for a product-specific time period to freeze the wart (20 seconds for Wartner; 40 seconds for Compound W).

• The process may be repeated after 10 days as many as three or four times for persistent warts.

• Caution: Do not use in children under age 4, diabetics, or pregnant or breastfeeding females; on the face, armpits, breasts, buttocks or genitals; on irritated skin; or on mucous membranes (e.g., mouth, nose, and anus).

26-10. Corns and Calluses

Introduction

Corns and calluses are excessive growth of the upper keratinized layer of the skin. They are more common in women than in men.

Diabetics have an increased incidence of calluses on their feet because of the loss of sensation, preventing them from noticing the pressure that would otherwise be uncomfortable.

Classification

• Hard corns (heloma durum): Corns overlying a bony prominence such as the toes or bottom of the heel

• Soft corns (heloma molle; interdigital corns): Corns between the toes (especially the fourth and fifth)

• Calluses (callosities): Superficial patches of hornified epidermis; flattened, but thickened with no central core

Clinical Presentation and Pathophysiology

Corns and calluses are caused by excessive growth of the upper keratinized layer of the skin (hyperkeratosis), resulting from friction or pressure, usually from improper or tight-fitting shoes.

Treatment

The only FDA-approved OTC medication is salicylic acid formulated in flexible collodion, plasters, disks, or pads.

Mechanism of action

Salicylic acid produces a keratolytic action, which increases hydration and lowers the pH of the outer skin, initially softening and then destroying the outer layer of skin.

Patient counseling

• Do not apply to irritated, infected, or reddened skin.

• If discomfort persists after using for 14 days, see a physician or podiatrist.

• Salicylic acid products are contraindicated in diabetics.

Adverse drug effects

Salicylic acid products are contraindicated in patients with diabetes and other patients with poor circulation because reduced sensation in the foot delays awareness of skin breakdown, allowing possible development of infection that can lead to sepsis. Refer diabetics to a physician or podiatrist for removal of corns or calluses.

OTC salicylic acid (SA) corn and callus products

• Freezone Corn and Callus Remover 13.6% SA

• Freezone One Step Corn Remover 40% SA

• Mediplast 40% SA plaster, cut to size

• Mosco Corn and Callus Remover 17.6% SA

• Off Ezy Corn and Callus Remover 17% SA

• One Step Callus Remover 40% SA

• Dr. Scholl's Corn and Callus Remover Liquid 12.6% SA

• Dr. Scholl's Corn or Callus Cushion Gel 40% SA

• Dr. Scholl's One Step Corn or Callus Remover Disc 40% SA

26-11. Key Points

Acne

• Acne occurs primarily in the teenage years because of the increase of androgens during puberty that produces increased activity of the sebaceous glands.

• Isotretinoin (Accutane) is the drug of choice for nodulocystic acne (type IV acne), which, if left untreated, will lead to extensive scarring.

• Isotretinoin is contraindicated in pregnancy because of the high incidence of serious birth defects.

• The most common side effects of isotretinoin are cheilitis (dry, chapped lips), dry skin, and dry eyes.

Fungal Infections of the Skin

• The most efficacious nonprescription topical antifungal is terbinafine (Lamisil).

• Systemic antifungal therapy is required for treatment of tinea capitis (ringworm of the scalp) and tinea unguium (fungal infection of the toenails and fingernails).

Hair Loss

• Androgenic alopecia—predominantly seen in males—is due to the conversion of testosterone to dihydrotestosterone, which binds to the hair follicles and causes them to produce progressively thinner hair.

• In the treatment of androgenic alopecia, minoxidil (Rogaine) should be applied and left on the scalp for 4 hours for maximum effects.

• Finasteride (Propecia) decreases the effect of androgens on hair follicles by inhibiting 5-α-reductase, which prevents the conversion of testosterone to dihydrotestosterone.

Dry Skin

• Dry skin occurs primarily in older adults because of decreased sebum production and decreased moisture-binding capacity of the skin.

• Products containing urea and lactic acid improve the skin's moisture-binding capacity, thereby increasing skin hydration.

Dermatitis

• Contact dermatitis, whether irritant or allergic, is initially treated with topical corticosteroid products.

• The absorption and subsequent adverse systemic effects of topical corticosteroids are increased in infant skin and with occlusion, the use of high-potency agents, and long-term use.

Poison Ivy, Poison Oak, and Poison Sumac

• Poison ivy, poison oak, and poison sumac are examples of causes of allergic contact dermatitis, which are the result of contact with the sap of plants of the genus Rhus.

• Severe cases of poison ivy, poison oak, or poison sumac require systemic corticosteroids to relieve symptoms, decrease the severity of the rash, and shorten the course of the disorder.

Scaly Dermatoses

• The cytostatic agents that suppress cell rate turnover—zinc pyrithione (Head and Shoulders) and selenium sulfide (Selsun Blue)—are the primary agents of choice for treatment of dandruff.

• Seborrhea usually requires topical corticosteroids or the topical antifungal ketoconazole for effective treatment.

• Psoriasis is a chronic inflammatory disease characterized by inflammation and silvery scales (known as plaques) with sharp delineated edges.

• Treatment of advanced psoriasis may require systemic corticosteroids or antimetabolites in addition to topical treatments for effective management of the disease.

Pediculosis

• Head lice (Pediculus humanus capitis) occur most commonly in elementary schoolchildren in the months of August and September.

• Permethrin (Nix) is the nonprescription agent of choice for treatment of head lice because it usually does not have to be repeated in 7-10 days as do other available nonprescription pediculicidal agents (synergized pyrethrins).

Corns and Warts

• Nonprescription products for the treatment of corns and warts contain salicylic acid.

• Self-treatment for corns or warts with over-the-counter agents is not recommended for diabetic patients because of reduced sensation in their feet that delays awareness of possible development of infections and can lead to sepsis.

• Warts result from an infection of the human papilloma virus and, therefore, are contagious and may spread on the body.

• Warts may be eliminated by surgery, freezing with liquid nitrogen (cryotherapy), or the direct application of caustics (e.g., salicylic acid, formalin, lactic acid, trichloroacetic acid, or podophyllin).

26-12. Questions

1.

Initial treatment of mild to moderate acne would include which of the following?

I. Topical antimicrobials

II. Topical retinoids

III. Isotretinoin

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

2.

Acne is due to which of the following?

I. Increased sebum production

II. Obstruction of hair follicle openings

III. Inflammation

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

3.

Patients using topical retinoids such as tretinoin (Retin-A) should be counseled to do which of the following?

I. Use sunblock before exposure to sunlight.

II. Do not use tretinoin with astringents, drying agents, or abrasive soaps.

III. Expect rapid improvement within 2 or 3 days of starting therapy.

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

4.

The most common side effects of isotretinoin (Accutane) include which of the following?

I. Cheilitis (dry chapped lips)

II. Acute depression

III. Decreased night vision

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

5.

Which of the following is an important contraindication and precaution to the use of isotretinoin?

A. Hypertension

B. Migraines

C. Allergic rhinitis

D. Pregnancy

E. Streptococcal infections

 

6.

Which of the following is the most efficacious nonprescription topical antifungal?

A. Tolnaftate (Tinactin)

B. Terbinafine (Lamisil)

C. Miconazole (Micatin)

D. Undecylenic acid (Desenex)

E. Clotrimazole (Lotrimin AF)

 

7.

Which of these fungal infections may be treated effectively with the use of topical antifungal agents?

I. Tinea capitis (ringworm of the scalp)

II. Tinea unguium (fungal infection of the toenails and fingernails)

III. Tinea corporis (ringworm of the skin)

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

8.

Tinea pedis is also known as

A. athlete's foot.

B. jock itch.

C. onychomycosis.

D. ringworm of the scalp.

E. ringworm of the skin.

 

9.

The treatment of choice for tinea unguium would be

A. clotrimazole.

B. miconazole.

C. undecylenic acid.

D. griseofulvin.

E. tolnaftate.

 

10.

All of the following are true regarding androgenic alopecia except

A. it is predominantly seen in males.

B. it is caused by the conversion of testosterone to dihydrotestosterone, which binds to the hair follicles, causing them to produce progressively thinner hair.

C. hair growth stimulation is temporary and lasts only as long as therapy continues.

D. hair loss in the frontotemporal area responds to treatment better than hair loss on the crown.

E. Early hair loss occurring recently in young males is more likely to respond than later hair loss at an older age.

 

11.

All of the following are true regarding the patient instructions for the proper use of minoxidil except

A. it should be applied on the scalp and left for 4 hours for maximum effect.

B. the patient should not swim, shampoo, or walk in rain soon after the application of minoxidil.

C. do not use on infected, irritated, inflamed, or sunburned skin.

D. the patient must continue therapy to maintain effectiveness.

E. women with alopecia should use the 5% strength of minoxidil rather than the 2% strength.

 

12.

Adverse effects of minoxidil include which of the following?

I. Hypertrichosis

II. Dermatitis and pruritus of the scalp

III. Hepatic damage

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

13.

The mechanism of action of finasteride (Propecia) to reduce male baldness is

A. a direct effect on hair follicles to deepen hair roots.

B. inhibition of the enzyme 5-α-reductase, which blocks the conversion of testosterone to dihydrotestosterone.

C. increased cutaneous blood flow to the hair follicles on the scalp because of vasodilation.

D. increased cutaneous blood flow to the hair follicles on the scalp because of opening the potassium channel.

E. increased development of new hair follicles on the scalp.

 

14.

All of the following are true regarding finasteride except

A. it is contraindicated in females of child-bearing age.

B. it was originally approved for treatment of benign prostatic hypertrophy.

C. improvement lasts only as long as treatment continues (new hair will be lost within 1 year of stopping treatment).

D. it must be taken on an empty stomach for complete absorption.

E. 2% of males report reversible sexual dysfunction while taking it.

 

15.

All of the following regarding dry skin are true except

A. it occurs primarily in older adults.

B. it occurs most commonly in the summer months.

C. it is caused by decreasing sebum production and decreased moisture-binding capacity of the skin.

D. flaking, scaling, xerosis, and pruritus are common manifestations of dry skin.

E. excessive cleansing and bathing removes lipids and worsens dry skin.

 

16.

All of the following statements are true regarding the treatment of dry skin except

A. hydrocortisone should be used only for short-term therapy of dry skin to relieve itching.

B. urea-containing products improve the skin's moisture-binding capacity.

C. lactic acid is a keratolytic agent that removes the upper epidermal skin cells and relieves the itching of dry skin.

D. emollients and moisturizers are helpful in the treatment of dry skin, especially when applied immediately after bathing.

E. although colloidal oatmeal may be helpful in the treatment of dry skin, patients should be cautioned about the possibility of falling because of a slippery bathtub.

 

17.

The agents of choice for the initial treatment of contact dermatitis, whether irritant or allergic, are

A. topical antihistamines.

B. oral antihistamines.

C. topical corticosteroids.

D. local anesthetics.

E. coal tar products.

 

18.

An increase in topical corticosteroid systemic absorption with subsequent systemic side effects may be seen in which of the following?

I. Occlusion

II. Infant's skin

III. Long-term use of high-potency agents

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

19.

All of the following are true regarding poison ivy except

A. it is an example of allergic contact dermatitis.

B. it is the result of contact with the sap of plants of the genus Rhus.

C. the treatment of choice is desensitization.

D. it may be caused by direct or indirect contact (e.g., with clothing or pets).

E. skin eruptions may occur from several hours up to 10 days following contact with the plants.

 

20.

The treatment of choice for severe or extensive cases of poison ivy or poison oak is

A. a local anesthetic such as benzocaine.

B. bentoquatam (Ivy Block).

C. a camphor and menthol antipruritic.

D. colloidal oatmeal.

E. a systemic corticosteroid.

 

21.

Which of the following agents for treatment of dandruff are cytostatic agents that suppress cell rate turnover?

I. Zinc pyrithione (Head and Shoulders)

II. Selenium sulfide (Selsun Blue)

III. Salicylic acid (Ionil)

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

22.

All of the following statements are true regarding seborrhea except

A. it is a chronic inflammatory skin disease seen in areas of greatest sebaceous gland activity.

B. it fluctuates in severity and is worsened by stress and poor health.

C. moderate to severe cases require topical corticosteroids or the topical antifungal ketoconazole for effective treatment.

D. it is called cradle cap when it occurs in infants.

E. it most commonly occurs on the legs and arms.

 

23.

Which of the following are characteristic of psoriasis?

I. Chronic inflammation

II. Silvery scales (known as plaques) with sharply delineated edges

III. Spontaneous exacerbations and remissions

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

24.

Treatment of advanced psoriasis may require topical therapy combined with which of the following systemic agents?

I. Corticosteroids

II. Antimetabolites such as methotrexate

III. Anthralin

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

25.

All of the following are true statements regarding head lice (Pediculus humanus capitisexcept

A. it occurs most commonly in elementary schoolchildren.

B. it occurs most commonly in the spring months of April and May.

C. it is transmitted by direct contact.

D. pruritus is the most common symptom.

E. head lice is the most common type of pediculosis infestation.

 

26.

All of the following statements are true regarding treatment of pediculosis with synergized pyrethrins (piperonyl butoxide and pyrethrins) except

A. inspect all family contacts, and treat if necessary.

B. apply after washing and drying the hair, and leave on overnight.

C. remove dead lice and nits after treatment with a lice or nit comb.

D. repeat treatment in 7-10 days.

E. avoid contact with the eyes, nose, and mouth.

 

27.

The most effective nonprescription agent for treatment of head lice is which of the following agents?

A. Permethrin (Nix)

B. Synergized pyrethrins (A-200)

C. Lindane (Kwell)

D. Ketoconazole

E. Salicylic acid

 

28.

Nonprescription products for the treatment of corns and warts contain which of the following agents?

A. Salicylic acid

B. Ketoconazole

C. Lactic acid

D. Acetylsalicylic acid

E. Hydrocortisone

 

29.

All of following are true statements regarding corns except:

A. They are excess growth of the upper keratinized layer of skin.

B. Salicylic acid is available in pads, disks, or flexible collodion for removal of corns.

C. Self-treatment for corns or warts with OTC agents is not recommended for diabetic patients because of the reduced sensation in their feet, which delays awareness of development of infections and may lead to sepsis.

D. They are contagious and may spread on the body.

E. They are usually caused by pressure or friction from improper or tight-fitting shoes.

 

30.

All of the following are true statements regarding warts except

A. they result from infection with the human papillomavirus.

B. they are contagious.

C. they may spread on the body.

D. plantar warts are located on the fingers, hands, and knees.

E. they are more common in children and immunocompromised patients.

 

31.

Warts may be eliminated by which of the following procedures?

I. Surgery

II. Freezing with liquid nitrogen (cryotherapy)

III. The direct application of caustics (e.g., salicylic acid)

A. I only

B. II only

C. III only

D. I and II

E. I, II, and III

 

26-13. Answers

1.

D. Topical antimicrobials and topical retinoids are the agents of choice for mild to moderate acne. Isotretinoin (Accutane) is reserved for nodulocystic acne (type IV acne), which, if left untreated, will lead to extensive scarring.

 

2.

E. Acne is primarily due to (a) hormonal changes occurring at or near puberty that increase sebum production and obstruct the hair follicle opening and (b) the breaking down of triglycerides to free fatty acids caused by enzymes from Propionibacterium acnes, which causes inflammation.

 

3.

D. Topical retinoid therapy will sensitize skin to ultraviolet light rays; therefore, patients should use sunblock prior to sun exposure. Patients using topical retinoids should use only mild soaps for cleansing the face and avoid astringents, drying agents, and abrasive soaps. Improvement will usually occur within 2-3 weeks after initiation of therapy.

 

4.

A. Cheilitis (dry chapped lips), together with dry skin and dry eyes, are the most common side effects of isotretinoin therapy.

 

5.

D. Isotretinoin is contraindicated in pregnancy because of the high incidence of serious birth defects.

 

6.

B. Terbinafine (Lamisil) is the most effective nonprescription topical antifungal.

 

7.

C. Topical antifungal agents are the first line of therapy against tinea corporis (ringworm of the skin). However, systemic antifungal therapy is usually required for treatment of tinea capitis (ringworm of the scalp) and tinea unguium (fungal infection of the toenails and fingernails).

 

8.

A. Tinea pedis is also known as athlete's foot.

 

9.

D. The treatment of choice for tinea unguium (fungal infection of the toenails and fingernails) is a systemic antifungal agent such as griseofulvin. Topical therapy is generally not effective for fungal infections of the nails.

 

10.

D. Hair loss in the crown responds to treatment better than hair loss of the frontotemporal areas.

 

11.

E. Women with alopecia should use only the 2% strength of minoxidil. Studies indicate that there is no greater degree of effectiveness with the 5% strength and the incidence of adverse effects (including increased growth of facial hair) is much greater in women using the 5% preparation.

 

12.

D. Common adverse effects of minoxidil include hypertrichosis (increased hair growth in areas other than the scalp) and dermatitis and pruritus of the scalp. Systemic side effects with topical minoxidil are rare and do not include hepatic damage.

 

13.

B. The mechanism of action of finasteride to reduce male baldness is blocking of the conversion of testosterone to dihydrotestosterone by inhibiting the enzyme 5-α-reductase.

 

14.

D. Finasteride does not have to be taken on an empty stomach. It may be taken with or without food. Finasteride was originally approved for treatment of benign prostatic hypertrophy. Improvement of alopecia lasts only as long as treatment continues, finasteride is contraindicated in females of childbearing age, and 2% of males report reversible sexual dysfunction.

 

15.

B. Dry skin occurs most commonly in the winter months and is often referred to as winter rash.

 

16.

C. Lactic acid is used in the treatment of dry skin, not as a keratolytic agent, but as an agent that increases skin hydration.

 

17.

C. Topical corticosteroids are the agents of choice for the initial treatment of irritant or allergic contact dermatitis. If the condition is severe or widespread, oral corticosteroids may be useful. Oral or topical antihistamines have minimal effect in the course of the treatment of contact dermatitis, possibly producing some antipruritic effect, but not affecting the course of the disorder.

 

18.

E. Topical corticosteroid systemic absorption is increased on an infant's skin and with occlusion, long-term use, and use of high-potency agents. Systemic corticosteroids' adverse effects may be severe and include adrenocortical suppression.

 

19.

C. Desensitization has no place in the treatment of poison ivy, and most studies indicate desensitization is not an effective method to prevent poison ivy.

 

20.

E. Systemic corticosteroids are the treatment of choice for severe or extensive cases of poison ivy or poison oak. Topical agents are limited in effectiveness and do not alter the course of the disease.

 

21.

D. Zinc pyrithione (Head and Shoulders) and selenium sulfide (Selsun Blue) are cytostatic agents used in the treatment of dandruff that suppress cell rate turnover. Salicylic acid is a keratolytic agent.

 

22.

E. Seborrhea most commonly occurs on the face, especially eyebrows and eyelashes, but not on the extremities.

 

23.

E. Psoriasis is a chronic inflammatory disease marked by silvery scales (known as plaques) with sharp delineated edges and characterized by spontaneous exacerbations and remissions.

 

24.

D. Treatment of advanced psoriasis may require topical therapy combined with either oral corticosteroids or antimetabolites such as methotrexate.

 

25.

B. Head lice occur most commonly in the months of August and September.

 

26.

B. Synergized pyrethrins should be applied after washing and drying the hair and left on for 10 minutes, not overnight.

 

27.

A. Permethrin (Nix) does not have to be repeated in 7-10 days as does the other available nonprescription pediculicidal agent, synergized pyrethrins (A-200). Lindane (Kwell) is not available over the counter, and significant neurologic toxicities have been reported with its use.

 

28.

A. Nonprescription products for the treatment of corns and warts contain salicylic acid as the active therapeutic agent.

 

29.

D. Corns are not contagious and may not spread on the body. Corns are an excess growth of the upper keratinized layer of skin, usually caused by pressure or friction from improper or tight-fitting shoes. Salicylic acid is available OTC for removal of corns in pads, disks, or flexible collodion. Self-treatment for corns or warts with OTC agents is not recommended for diabetic patients because of the reduced sensation in their feet, which delays awareness of the development of infections and could lead to sepsis.

 

30.

D. Plantar warts are not located on the fingers, hands, or knees; they are located on the soles of the feet.

 

31.

E. Warts may be eliminated by surgery, freezing with liquid nitrogen (cryotherapy), or direct application of caustics (e.g., salicylic acid).

 

26-14. References

Arndt KA. Manual of Dermatologic Therapeutics. 5th ed. Boston: Little, Brown; 1995.

Arndt KA, Wintroub BU, Robinson JK, et al., eds. Primary Care Dermatology. Philadelphia: WB Saunders; 1997.

Berardi RR, Ferreri SP, Hume AL, et al., eds. The Handbook of Nonprescription Drugs. 16th ed. Washington, D.C.: American Pharmaceutical Association; 2009.

Burnham TH, ed. Drug Facts and Comparisons. Baltimore: Lippincott Williams & Wilkins; 2005.

Champion RH, Burton JL, Burns DA, eds. Textbook of Dermatology. 6th ed. Oxford, U.K.: Blackwell Scientific Publications; 1998.

Covington, TR. Nonprescription Drug Therapy: Guiding Patient Self-Care. Baltimore: Lippincott Williams & Wilkins; 2003.

DiPiro JT, Talbert RL, Yee GC, et al., eds. Pharmacotherapy: A Pathophysiologic Approach. 5th ed. Stamford, Conn.: Appleton & Lange; 2004.

Epstein E. Common Skin Disorders. 6th ed. Philadelphia: WB Saunders; 2008.

Fitzpatrick JE. Dermatology Secrets in Color. 2nd ed. Philadelphia: Hanley and Belfus; 2001.

Freedberg IM, Eisen AZ, Wolff K, et al., eds. Fitzpatrick's Dermatology in General Medicine. 5th ed. New York: McGraw-Hill; 1999.

Habif TP, Campbell JL, Quitadamo MJ. Skin Disease: Diagnosis and Treatment. St. Louis, Mo.: Mosby; 2001.

Herfindal T, Gourley D, eds. Textbook of Therapeutics. 6th ed. Baltimore: Lippincott Williams & Wilkins; 2000.

Odom RB, James WD, Berger TG, eds. Andrew's Diseases of the Skin: Clinical Dermatology. Philadelphia: WB Saunders; 2000.

Pray WS. Nonprescription Product Therapeutics. Hagerstown, Md.: Lippincott Williams & Wilkins; 1999.

Top OTC/HBC brands in 2002. Drug Topics. 2003; 145:33-34.

Wolverton SE, ed. Comprehensive Dermatologic Drug Therapy. Philadelphia: WB Saunders; 2001.