Clinical Subtypes of Medication Overuse Headache - Findings From a Large Cohort.

In this study on a large and very well characterized population of MOH, we describe the distinctive clinical characteristics of MOH subtypes. These findings contribute to more clearly define the clinical picture of a poorly delineated headache disorder. They also provide some insights in the possible trajectories leading to this highly disabling chronic headache, that is classified as a secondary form, but whose occurrence is entirely dependent on an underlying primary headache.