BMA Concise Guide to Medicine & Drugs


Brand names Andropatch, Intrinsa, Nebido, Restandol Testocaps, Striant SR, Sustanon, Testim, Testogel, Tostran

Used in the following combined preparations None


Drug group Male sex hormone

Overdose danger rating Low

Dependence rating Low

Prescription needed Yes

Available as generic Yes


Testosterone is a male sex hormone produced by the testes and, in small quantities, by the ovaries in women. The hormone encourages bone and muscle growth in both men and women and stimulates sexual development in men.

The drug is used to treat testosterone deficiency (hypogonadism) due to pituitary or testicular disorders. It is also used to initiate puberty in male adolescents if it has been delayed due to deficiency of the natural hormone.

Testosterone can interfere with growth or cause over-rapid sexual development in adolescents. High doses may cause deepening of the voice, excessive hair growth, or hair loss in women.


Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Injection, implanted pellets, gel, patch, oral and buccal preparations.

Frequency and timing of doses Varies according to preparation and condition being treated (injection); 5g daily, according to response, to maximum of 10g daily (gel); every 6 months (implant); once daily (patch).

Dosage range Varies with method of administration and the condition being treated.

Onset of effect 2–3 days. Full effect may take several months.

Duration of action 1 week to more than 3 months (injection); approximately 6 months (implant).

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children. Protect from light.

Missed dose No cause for concern, but take as soon as you remember.

Stopping the drug Do not stop taking the drug without consulting your doctor.

Exceeding the dose An occasional unintentional extra dose is unlikely to be a cause for concern. But if you notice unusual symptoms, or if a large overdose was taken, notify your doctor.


Most of the more serious adverse effects of testosterone are likely to occur only with long-term treatment and may be helped by a reduction in dosage. Acne and skin irritation with the gel or patches are common adverse effects. More rarely, hair loss, mood changes, and water retention may occur. Discuss with your doctor if any of these are severe. If your develop jaundice, stop using the drug and contact your doctor promptly. In men, the drug may also cause abnormal erections, breast development, and difficulty in passing urine; if these occur, they should be reported to your doctor. In women, additional adverse effects include unusual hair growth or hair loss, deepening of the voice, and enlargement of the clitoris; these should also be reported to your doctor.


Anticoagulants Testosterone may increase their effect, requiring adjustment of their dosage.

Antidiabetics Testosterone enhances their effects, requiring reduction of their dosage.


Be sure to tell your doctor if:

· You have long-term liver or kidney problems.

· You have heart problems.

· You have prostate trouble.

· You have high blood pressure.

· You have epilepsy or migraine headaches.

· You have diabetes.

· You are taking other medicines.

Pregnancy Not prescribed. Avoid skin-to-skin transfer of testosterone from other people.

Breast-feeding Not prescribed. Avoid skin-to-skin transfer of testosterone from other people.

Infants and children Not prescribed for infants and young children. Reduced dose necessary in adolescents.

Over 60 Rarely required. Increased risk of prostate problems in elderly men. Reduced dose may therefore be necessary.

Driving and hazardous work No special problems.

Alcohol No special problems.


Prolonged use of this drug may lead to reduced growth in adolescents. In older men, it may accelerate prostate disease.

Monitoring Regular blood tests for the effects of testosterone treatment are necessary, such as red blood cell count, electrolyte levels, liver function tests, and PSA (prostate-specific antigen) levels.