antihistamine | Pharmacology Mentor

Pharmacology of Levocetirizine

December 27, 2025December 18, 2023 by Pharmacology Mentor

Introduction Levocetirizine is a widely used second-generation H1-antihistamine, often prescribed for the management of allergic rhinitis, urticaria, and other allergic conditions. It is the active R-enantiomer of its racemic counterpart, cetirizine, a drug that has long been established in clinical practice. By isolating the pharmacologically more potent R-enantiomer, levocetirizine offers an improved therapeutic profile, characterized by high efficacy and reduced … Read more

Pharmacology of Diphenhydramine

December 28, 2025November 11, 2023 by Pharmacology Mentor

Introduction Diphenhydramine is a prototypical first-generation antihistamine with a long history of clinical use for allergic reactions, insomnia, motion sickness, and a variety of off-label applications. Its popularity in both prescription and over-the-counter preparations is a testament to its versatility, but its significant sedative and anticholinergic properties necessitate a deep understanding for safe and effective use. … Read more