Antiallergic activity of loratadine a non sedating antihistamine
These drugs also offer the advantage of once daily dosing.
Since there is no Indian report of a comparative trial of these drugs in chronic urticaria, we performed a randomized investigator-blinded parallel group study to compare their efficacy and side effects in the treatment of this common condition.
Indian J Dermatol Venereol Leprol [serial online] 1998 [cited 2017 May 24];-6. 1998/64/1/12/4632In urticaria, H1 receptors mediate the pruritic, vasodilatory and vasopermeable actions of histamine.[1-3] Apart from their specific H1 receptor inhibitory action, the first generation H1 antagonists also activate muscarinic, cholinergic, serotonergic and alpha-adrenergic receptors, leading to side effects. The second generation antihistamines cetirizine and loratadine selectively antagonise H1 receptors lessening the possibility of side effects.The newer, second-generation (ie, nonsedating) antihistamines are usually preferable to avoid sedation and other adverse effects associated with the older, first-generation antihistamines.Ocular antihistamine drops (for eye symptoms), intranasal antihistamine sprays, intranasal cromolyn, intranasal anticholinergic sprays, and short courses of oral corticosteroids (reserved for severe, acute episodes only) may also provide relief.It is also effective in alleviating symptoms of allergic rhinitis such as sneezing, nasal discharge, itching, ocular itching and burning.Nasal and ocular sign and symptoms are relieved rapidly after oral administration.