- Clinical science
Medication-overuse headache (MOH) is a chronic secondary headache disorder caused by regular overuse of analgesics that are used to treat a preexisting chronic headache disorder. The most common underlying headache disorders are migraine followed by tension-type headache. Simple analgesics (e.g., acetaminophen, NSAIDs) alone or in combination with caffeine, followed by triptans, are the most commonly overused medications. Women aged 40–49 years are most commonly affected. The pathophysiology is not completely understood but likely involves dependence processes, central sensitization, and (possibly) genetic predisposition. The diagnosis is based on clinical criteria. Diagnostic studies are usually not necessary unless indicated to investigate the cause of the preexisting chronic headache. Treatment involves patient education, weaning of overused medications, management of withdrawal symptoms, and relapse prevention. MOH typically resolves with discontinuation of the overused medications.
Risk factors 
- Preexisiting chronic headache disorder: Most commonly migraine followed by tension-type headache.
- Prolonged overuse of symptomatic headache medications : Most commonly simple analgesics (i.e., acetaminophen, NSAIDs) alone or in combination with caffeine, followed by triptans.
- Female sex
- Physical inactivity
- Regular use of tranquilizers
- Only partially understood. Pathogenesis may involve dependence processes, central sensitization, and possibly genetic predisposition.
Medication-overuse headache is characterized by an increase in headache frequency and severity, and increasing refractoriness to abortive and prophylactic pain medications in patients with a prolonged history of chronic headache and medication overuse. 
- Headache characteristics may differ from the underlying chronic headache and often include:
- Autonomic and vasomotor symptoms can occur (e.g., tachycardia, nausea, vomiting, rhinorrhea)
- Comorbid anxiety and depression
- Behavior may mimic that seen with other substance dependence. 
All the following 4 criteria must be fulfilled:
- History of preexisting headache disorder
- Regular overuse of medications for > 3 months taken to acutely relieve headaches
- Headache occurs on ≥ 15 days per month.
- Headache is not better explained by another headache diagnosis (See and for an overview, and see a for a detailed list).
Patient education followed by reduction and discontinuation of overused medications are the mainstays of treatment and typically lead to the resolution of medication-overuse headaches.
General principles 
- Patient counseling should be emphasized.
- Complete weaning of the overused medication is essential.
- The rate (abrupt vs. gradual) and setting (outpatient vs. inpatient) of medication withdrawal is determined based on patient characteristics and the overused medication class.
- Headache medications and analgesics are preferably avoided during the withdrawal period.
- Supportive interventions may include:
- Expert consultation is advised for patients who have previously been unable to discontinue medications or have a history of severe withdrawal symptoms.
Key points for patient education and counseling 
- Explain the exacerbating effects of medication overuse.
- Emphasize the benefits of weaning and nonpharmacological therapy.
- Review specific treatment goals, including:
- Weaning schedule
- Withdrawal symptom management
- Relapse prevention and maintenance
- Manage expectations regarding withdrawal.
- Ensure regular follow-up.
Discontinuation of overused medications
- Medication withdrawal
- Withdrawal symptoms (usually last for a few days, but may persist for up to 4 weeks) 
Rescue medications 
- Analgesics for severe withdrawal headaches
- When necessary, additional symptom-based treatment can include tranquilizers, neuroleptics, and/or IV hydration. 
- Short-term bridging medication: used to prevent withdrawal headaches. 
Avoid medications of the same class as the overused medication. 
Management of the underlying chronic headache 
- Nonpharmacological interventions
Long-term prophylactic medications
- Consider adding prophylactic headache medications for patients with prior difficulty or inability to discontinue medication.
- Medication choice is based on the type of headache, side-effect profile, comorbidities, and previously tried prophylactic therapies. 
- See , , and “Treatment” section in .
Disposition and referrals 
- Outpatient treatment with primary care provider follow-up and counseling is appropriate for most patients.
- Consider inpatient supervised withdrawal for patients with any of the following:
- Consider short-term psychotherapy and/or other nonpharmacological therapy referrals. 
- Consider consulting a neurologist or headache specialist for patients with prior difficulty or inability to discontinue medication.
- Primary prevention 
Secondary prevention 
- Limit the use of headache symptomatic medications to no more than 2 days per week.
- Avoid previously overused medication classes.