A single-centre, randomized, placebo-controlled trial is proposed to assess Frovatriptan as a transitional therapy in patients diagnosed with medication overuse headache. Currently, there are no proven transitional therapies to help patients get through the detoxification process. Frovatriptan has not been tested as a transitional therapy in the past. This study will compare Frovatriptan, taken over a 10 day transitional period, to placebo. The primary outcome of the study will be the mean headache intensity in the 10 day transitional period in the Frovatriptan group as compared to the placebo group. A number of secondary and exploratory outcomes will also be determined and further data collection will occur at 1, 2, and 3 month periods. The duration of the study for the participants will be 3 months, and they will be asked to keep detailed headache diaries during this time. Ten days of baseline headache diaries will also be performed before patients can enter the study.