The Efficacy of Japanese Herbal Kampo Medicine as an Acute and Prophylactic Medication to Treat Chronic Daily Headache and Medication Overuse Headache:-Single Arm Retrospective Study.

Introduction A chronic daily headache (CDH) comprises a group of headaches occurring at least 15 days per month for three or more consecutive months. We retrospectively investigated the effectiveness of the hybrid treatment strategy for CDH using Kampo medicine combined with Western medication. Methods We retrospectively investigated 43 consecutive first-visit CDH patients. In addition to Western acute and prophylactic medications, we prescribed three types of Kampo medicines: goreisan, goshuyuto, and kakkonto depending on the patients' symptoms. Headache impact test-6 (HIT-6), monthly headache days (MHD), monthly migraine days (MMD), and monthly acute medication intake days (AMD) before, 1- and 3-months after starting the hybrid medications were assessed as outcomes. Results Thirty-six women and seven men were included. The median age was 51 years old. Nine were chronic migraine (CM), 22 were episodic migraine and tension-type headaches (EM+TTH), and 12 were chronic TTH. Twenty-seven patients also had medication overuse headaches (MOH). The medians of HIT-6 before, one and three months after treatment were 63, 48, and 40, respectively. Those of MHD were 20, 5, and 2. Those of MMD were 2, 0, and 0. Those of AMD were 15, 0, and 0. Significant reductions in HIT-6, MDH, MMD, and AMD were observed one and three months after starting Kampo treatment. Similar trends were observed in the EM+TTH and MOH patients as subgroup analyses. Conclusion The hybrid medication strategy of Kampo and Western medicines for CDH is safe and effective in terms of both acute and prophylactic medications with rapid efficacy.