Potential of interaction between the H1-antagonist astemizole and other drugs.

Astemizole is a potent H1-antagonist devoid of sedative effects, which was found at single oral daily doses to be very effective in the treatment of allergic rhinitis, allergic conjunctivitis, and urticaria. Its interaction potential on other drugs was studied in various ways. Studies on salivary antipyrine clearance, the 6-beta-hydrocortisol excretion, the elimination rate of ethanol and the indocyanine-green clearance are presented. No changes were observed. Astemizole also was given in combination with diazepam or alcohol. Psychomotor performance failed to show any effects. In none of these studies was there any evidence of interaction of astemizole on other drugs. This review summarizes the data available thus far.