Reply

Dear sir We appreciate the comments of Drs Allen et al. We agree that the small numbers involved in our study could prevent demonstration of a significant drug effect over placebo, as we pointed out in the Discussion. In addition, the high placebo response (50%) requires a greater number of patients to demonstrate significance.

As we discussed in the paper, there are notable differences between our study and that of Ahrens et al. (1) That study clearly demonstrated the effectiveness of the rizatriptan wafer vs. placebo. The purpose of further placebo-controlled studies would be to examine the outcomes when the rizatriptan wafer was taken at the onset of the headache, as is generally recommended in clinical practice.

The purpose of our report was not to deny the efficacy of rizatriptan wafer, but to explore the effects of very early administration, and in particular, the high placebo response under the conditions of our study.