Astemizole. Its use in the treatment of patients with chronic vertigo.

Thirty-eight patients with chronic vertigo and positional and/or spontaneous nystagmus finished a double-blind study to determine the efficacy of astemizole on nystagmus and its symptoms. Patients with Meniere's disease were excluded. The study took 13 weeks with a follow-up examination. Six to eight noncaloric electronystagmograms were recorded at determined intervals. Three doses of the drug, 5, 10, and 20 mg/d, and placebo were tested. A patient was considered a responder if the number of nystagmic beats occurring in eight head and body positions was reduced by 50% or more and the symptoms of vertigo were greatly reduced. Twenty-eight of the 38 patients were responders. Blood levels of astemizole were related to effectiveness. Patients did not respond to placebo. The onset of drug effect was slow. Astemizole appears to be useful and safe to try on the patient with chronic dizziness.