Desloratadine

Desloratadine (Sch34117) is an orally active and selective H1 receptor antagonist (K_i=0.9 nM) with anti-inflammatory and anti-allergic activities. Desloratadine inhibits the release of histamine and LTC4 from human basophils and targets the regulatory signals of IL-4 and IL-13 production in basophils. Desloratadine significantly alleviates SAR symptoms in patients with concurrent asthma and can be used in the study of seasonal allergic rhinitis and chronic idiopathic urticaria^{[1][2][3][4][5][6]}. In Vitro:Desloratadine (300 nmol/L-100 µmol/L) inhibits the release or production of multiple inflammatory mediators in cells with high affinity receptors for IgE^[1].
Desloratadine (1-10 μM, 15 min) has an inhibitory effect on IGE-induced IL-4 and IL-13 secretion that is nearly 6-7 times greater than its inhibitory effect on histamine and LTC4 release^[2].
Desloratadine (0.1-10 μmol/L, 1 h) dose-dependently inhibits platelet-activating factor (PAF)-induced eosinophil chemotaxis and TNF-α-induced eosinophil adhesion to human umbilical vein endothelial cells^[5].
Desloratadine (1, 10 and 50 μM, 30 min) inhibits the activation of eosinophils and mast cells in polyp tissues of patients with chronic sinusitis^[6].
In Vivo:Desloratadine inhibits histamine-induced paw edema in a mouse inflammatory model in a dose-dependent manner (ED₅₀=0.15 mg/kg; p.o.) and dose-dependently reduces the number of coughs after ovalbumin (HY-W250978) sensitization and antigen challenge in sensitized guinea pigs (the minimum effective antitussive dose is 0.3 mg/kg)^[5].