Six males and one female with chronic tic disorders, whose ages ranged from 12 to 31 years, were evaluated before treatment, after 1 month on placebo, after a single 10 mg nifedipine dose (three patients), and monthly while on flunarizine 10-15 mg (mean dose of 13 mg). None of the patients receiving nifedipine improved, but treatment with flunarizine significantly decreased both motor and phonic tic severity and frequency in all but one patient. Side effects included mild transient headaches in one patient, depression in one, and bradykinesia in two. Although a double-blind study is essential to validate our findings, results suggest that flunarizine is a useful drug in the treatment of Gilles de la Tourette syndrome.