Medication-overuse headache: Bridging therapies for detoxification.

Medication-overuse headache (MOH) or rebound headache is caused by frequent use of acute pain medications and often complicates chronic migraine. The exact cause for this association remains unknown but is likely to represent complex interplay between psychosocial factors, class of medication overused and the presence of polymorphic gene variants of pain pathways involved in migraine. The most important treatment strategy for MOH is withdrawal (also known as detoxification) of the overused acute medication, which has repeatedly been shown to achieve a significant reduction in monthly headache days at 8 weeks. Reducing or stopping acute medication, however, typically worsens pre-existing headache and depending on the class of medication overused, may also cause psychological and physical symptoms. Numerous 'bridging' therapies have been used to try and reduce the frequency and intensity of withdrawal headaches and the severity of accompanying symptoms to aid successful withdrawal. The aim of this narrative review was to examine the withdrawal process for different classes of acute medication and examine different pharmacological and non-pharmacological bridging therapies in MOH.