Abstract
Dear Sir Thank you for the opportunity to reply to the letter by Bigal et al. published in this issue of Cephalalgia.
Overall, our patients had a relative reduction in headache frequency from the first visit to discharge from our out-patient clinic of 46%, varying from 30% for tension-type headache (TTH), 55% for mixed migraine and TTH and 64% for pure migraine (1). Our patients were completely drug free during a 2-month detoxification period and then followed for an average time of 228 days (1). If one adds the 2 months undergoing medication withdrawal, the time frame is very similar to the 1-year follow-up reported by Bigal et al. (2). We did not compare the outcome already after 2 months' drug withdrawal. The outcome following the 2 months' drug-free period has been described in an earlier report (3).
These factors mean that there is an even greater agreement between the two studies than suggested by Bigal et al. Together, the two studies provide strong evidence that patients with medication overuse must be withdrawn from overuse before they can fully benefit from preventive therapy.