Medication-overuse headache.

Medication-overuse headache (MOH) can be caused by almost all anti-headache drugs including analgesics, ergots, triptans, and combined preparations The prevalence of chronic daily headache (CDH) appears to be between 2% and 4% in the general population. Current epidemiologic studies suggest that MOH accounts for approximately 50% of these cases. The pathophysiology of MOH remains unclear. The only therapy is withdrawal from the overused substances. Prednisone decreases the duration of headache in the first days of withdrawal therapy. The only strategy to reduce the prevalence of MOH is to prevent the development of MOH in the first place by restriction of anti-headache drugs and constant education of patients.