BMA Concise Guide to Medicine & Drugs


Brand names [loratadine] Boots Hayfever and Allergy Relief All Day, Clarityn, Clarityn Allergy; [desloratadine] NeoClarityn

Used in the following combined preparations None


Drug group Antihistamine

Overdose danger rating Low

Dependence rating Low

Prescription needed No (loratadine); Yes (desloratadine)

Available as generic Yes


Loratadine, a long-acting antihistamine drug, is used for the relief of symptoms associated with allergic rhinitis, such as sneezing, nasal discharge, and itching and burning of the eyes. Symptoms are normally relieved within an hour of oral administration. Loratadine is also used to treat allergic skin conditions such as chronic urticaria (itching). An advantage of loratadine over older antihistamines, such as chlorphenamine, is that it has fewer sedative and anticholinergic effects, so this drug is less likely to cause drowsiness.

Desloratadine is the active breakdown product of loratadine. It is available as a separate product (NeoClarityn) but offers no advantages over loratadine itself.

Loratadine and desloratadine should be discontinued about four days prior to skin testing for allergy as they may decrease or prevent the detection of positive results.


Follow instructions on the label. Call your doctor if symptoms worsen.

How taken/used Tablets, liquid.

Frequency and timing of doses Once daily.

Adult dosage range 10mg daily (loratadine); 5mg daily (desloratadine).

Onset of effect Usually within 1 hour.

Duration of action Up to 24 hours.

Diet advice None.

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

Missed dose Take as soon as you remember. If your next dose is due within 6 hours, take a single dose now and skip the next.

Stopping the drug Can be safely stopped as soon as you no longer need it.

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


Adverse effects are rare with loratadine/desloratadine. They include fatigue, nausea, headache, dry mouth, palpitations, and fainting. If either of the last two occur, consult your doctor.


Cimetidine, clarithromycin, erythromycin, ketoconazole, fluoxetine, fluconazole, quinidine, and fosamprenavir These drugs may increase the blood levels and effects of loratadine and desloratadine, but this has not been found to cause problems.


Be sure to consult your doctor or pharmacist before taking this drug if:

· You have liver disease.

· You are taking other medicines.

Pregnancy Safety in pregnancy not established. Discuss with your doctor.

Breast-feeding Safety not established. The drug passes into the breast milk. Discuss with your doctor.

Infants and children Not recommended under 2 years (loratadine). Not recommended under 1 year (desloratadine).

Over 60 No problems expected.

Driving and hazardous work Problems are unlikely, but be aware of how the drug affects you before driving or carrying out hazardous work.

Alcohol Alcohol will increase any sedative effects of loratadine/desloratadine.


No problems expected.