Medications and Drugs

GENERIC NAME: desloratadine

BRAND NAME: Clarinex

DRUG CLASS AND MECHANISM: Desloratadine is an oral, long-acting antihistamine that is similar chemically to loratadine (Claritin). It is used to treat the symptoms caused by histamine. Histamine is a chemical that is responsible for many of the signs and symptoms of allergic reactions, for example, swelling of the lining of the nose, sneezing, and itchy eyes. Histamine is released from histamine-storing cells (mast cells) and then attaches to other cells that have receptors for histamine. The attachment of the histamine to the receptors causes the cell to be "activated," releasing other chemicals which produce the effects that we associate with allergy. Desloratadine blocks one type of receptor for histamine (the H1 receptor) and thus prevents activation of H1 receptor-containing cells by histamine. Desloratadine does not readily enter the brain from the blood and, therefore, causes less drowsiness (sedation). It is a member of a small family of non-sedating antihistamines which includes loratadine (Claritin), cetirizine (Zyrtec), and azelastine (Astelin). Desloratadine was approved by the FDA in December, 2001.

PRESCRIPTION: Yes

GENERIC AVAILABLE: No

PREPARATIONS: Tablets, 5 mg and syrup, 0.5mg/1mL 

STORAGE: Store tablets and syrup at 25°C (77°F).

PRESCRIBED FOR: Desloratadine is used for the treatment of allergies and chronic urticaria (hives) in adults and children 12 years of age or older.

DOSING: The recommended dose for adults and children 12 years or older is 5 mg daily.  Syrup can be used for children two years and older with the dose dependent on the age of the child.  Desloratadine can be taken with or without food.

DRUG INTERACTIONS: In controlled clinical studies there were no interactions with other drugs that affected the safety or effectiveness of desloratadine.

PREGNANCY: Desloratadine has not been studied in pregnant women.

NURSING MOTHERS:Desloratadine passes into breast milk and should therefore be used with caution in nursing mothers.

SIDE EFFECTS: The most common side effects of desloratadine are weakness, sore throat, dry mouth and sleepiness.

Medical Author: Omudhome Ogbru, Pharm.D.
Medical Editor: Jay Marks, M.D.

Reference: FDA Prescribing Information

Last Editorial Review: 5/26/2002 10:09:02 PM

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