Abstract
Histamine(1), receptor antagonists are being prescribed frequently in ENT practice. However, previously we found a fall of blood glucose with terfenadine and astemizole. Present study (double blind, randomized, single dummy and placebo controlled) evaluated the chronic effect (7 days of use) of clemastine, Loratidine and Certrizine on blood glucose level in patient of allergic rhinitis. Cetrizine produced a significant increase in post-prandial blood glucose (P<0.02) and a little rise in fasting blood glucose. Clamastine caused a little fall of fasting and a little rite of post-prandial blood glucose levels. The exact mechanisms involved in the effect of these drugs on blood glucose remain to be elucidated.