Toxicity of drugs used for treatment of rhinitis: a reminder to the otorhinolaryngologist.

We retrospectively studied files on toxicity of drugs used for treatment of rhinitis (nasal antihistamines, oral antihistamines, nasal vasoconstrictors, oral decongestants, nasal corticosteroids, nasal anticholinergic agent, nasal mast cell stabilizer, and respiratory antigen preparations for oral use) that occurred in São Paulo, Brazil, from 1 July 1996 to 30 June 1998. There were 823 cases of toxicity by these agents, with a predominance of oral decongestants (in combination with antihistamines) (53.4%). There was a significant incidence of toxicity within children aged 1 to 4 years (P < 0.05) and a preponderance among males aged 5-9 years and females aged 10-39 years. Accidental intake of medicines accounted for the majority of toxicity cases (57.2%).