The velocity step test. Its use in the evaluation of the effects of drugs in dizzy patients.

The effect of flunarizine (10 mg/day) was studied in open and double-blind clinical trials. Patients presenting the symptom of dizziness were diagnosed as having the hyperventilation syndrome. They showed vestibular hyperreactivity in the velocity step test. This test was performed before and after 4-6 weeks of treatment. The results of treatment were compared with a control or placebo group. In an open trial, 12 of 14 patients reported alleviation of dizziness during treatment and showed a significant decrease in right-left asymmetry of their velocity step responses. In a double-blind trial, no significant difference in effects or side effects was found between the drug and placebo groups.