A double-blind cross-over study with clonazepam (Rivotril) 0.5 mg b.i.d. versus placebo was carried out in 38 migraine patients. After a pre–test period of 4 weeks, Rivotril 1 mg per day and placebo were given during a 4 week period each, in a randomized fashion; thereafter Rivotril 2 mg per day was given for 4 weeks in a semi-blind fashion.

With regard to headache days, the results for both I and 2 mg Rivotril differed significantly (p<0.05) from the pre–test status, whereas with regard to the headache index, only the result for 2 mg differed significantly from pre-test results. When the placebo results (and not the pre–test results) were used, no significant difference was found with either 1 or 2 mg Rivotril.

More than half the patients complained of some drowsiness on Rivotril medication, particularly in the initial phase. Eighteen patients continued with Rivotril medication on a long–term basis in an open trial with some beneficial effect and less side–effects.