Which is not a second generation antihistamine?
High-Yield Explanation
First-generation H1 antagonists (e.g., dimenhydrinate, cyclizine, meclizine, and promethazine) can prevent motion sickness, although scopolamine is more effective. Antiemetic effects of these H1 antihistamines can be beneficial in treating veigo or postoperative emesis. Cimetidine, ranitidine, famotidine, and nizatidine are selective competitive inhibitors of histamine on H2 receptors. These receptors modulate smooth muscle, vascular tone, and gastric secretions and may be involved in clinical effects associated with anaphylactic and anaphylactoid reactions as well as ingestion of histamine or histamine-like substances. FIRST-GENERATION H1 BLOCKERS Hydroxyzine Diphenhydramine Promethazine Cyproheptadine Doxepin SECOND-GENERATION H1 BLOCKERS Cetirizine Levocetirizine Loratadine Desloratadine Fexofenadine Acrivastine Ref: Burkha C., Morrell D., Goldsmith L. (2011). Chapter 65. Dermatological Pharmacology. In L.L. Brunton, B.A. Chabner, B.C. Knollmann (Eds), Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e.