Desloratadine

Desloratadine (trade name Clarinex and Aerius) is a tricyclic H1 antagonist that is used to treat allergies. It is an active metabolite of loratadine. Desloratadine (trade name Clarinex and Aerius) is a tricyclic H1 antagonist that is used to treat allergies. It is an active metabolite of loratadine. It was patented in 1984 and came into medical use in 2001. Desloratadine is used to treat allergic rhinitis, nasal congestion and chronic idiopathic urticaria (hives). It is the major metabolite of loratadine and the two drugs are similar in safety and effectiveness. Desloratadine is available in many dosage forms and under many trade names worldwide. An emerging indication for desloratadine is in the treatment of acne, as an inexpensive adjuvant to isotretinoin and possibly as maintenance therapy or monotherapy. The most common side-effects are fatigue, dry mouth, and headache. A number of drugs and other substances that are prone to interactions, such as ketoconazole, erythromycin and grapefruit juice, have shown no influence on desloratadine concentrations in the body. Desloratadine is judged to have a low potential for interactions. Desloratadine is a selective H1-antihistamine which functions as an inverse agonist at the histamine H1 receptor. At very high doses, is also an antagonist at various subtypes of the muscarinic acetylcholine receptors. This effect is not relevant for the drug's action at therapeutic doses. Desloratadine is well absorbed from the gut and reaches highest blood plasma concentrations after about three hours. In the bloodstream, 83 to 87% of the substance are bound to plasma proteins.