Neuropsychologic and cardiovascular effects of clemastine fumarate under pressure

Allergic rhinitis and mild respiratory infections have been widely accepted as temporary contraindications for fitness to dive. Nonetheless, several sport and professional divers use antihistamines to ease ear, nose, and throat (ENT) problems, especially for opening tubal ostium. Some divers know they are unfit to dive, but for a variety of reasons (e.g., money or short holiday) they try to clear their ears. Thus, the use of antihistaminic drugs (like clemastine fumarate) is common during diving. This double-blind, crossover study indicates that this special antihistamine does not increase the sedative effects of nitrogen narcosis, nor does it increase the level of cardiac arrhythmias. Liberal use of antihistamines while diving cannot be recommended because of possible complications connected with different preparations and the temporary limitations they impose on the diver.