Analgesic Rebound Headache

See related article: headache due to substance or its withdrawal.

Rebound headaches after analgesics are common. They are usually intermittent tension-type headaches. Patients with frequent headaches (e.g. tension headaches or migraine) self medicate to pre-empt or cure headache and a vicious cycle occurs, of analgesia, rebound headache and more analgesia.¹ All simple analgesics, especially those with narcotic content, and probably non-steroidal anti-inflammatory drugs, ergotamine, caffeine and tryptans are implicated.² Rebound headaches may occur after only a few days of analgesic dosing per week.³

• About 20% of patients with chronic headaches and most with daily headaches have analgesic rebound headaches.^4,5
• Low doses daily carry greater risk than larger doses taken weekly.
• Patients are most commonly migraine or tension headache sufferers in the 30-40 year age group.
• Medication overuse headache affects more women than men (5:1).
• Compound analgesics are more likely to induce analgesic rebound headaches that the use of just single medications.
• Analgesic rebound headaches may be a common cause of post-traumatic headaches.⁶

• Diagnosis is made from the history and having a high level of suspicion:
• Daily or almost daily headache, with daily use of analgesic medication. A prospective diary record over two weeks may help the drug history.
• Many patients with medication overuse headache use large quantities of drug and multiple analgesic agents.
• The headache is often worst on waking in the morning and often increased after physical exertion.
• There is often a history of superimposed vascular or migraine-type headaches in addition to the baseline daily headache. The history may begin with episodic headache months or years earlier.
• Depression and sleep disturbances frequently co-exist.

Differential diagnosis includes any cause of regular headache from migraines, tension headache and chronic sinusitis to intracranial pathology and space occupying lesions.

• Diagnosis is clinical.
• Investigations are directed towards possible alternative diagnoses.
• Secondary problems from chronic analgesia abuse such as liver or kidney damage may need to be excluded.

• Patient education and withdrawal of the offending drug and psychological support is the cornerstone of treatment.
• Most respond fairly rapidly to the withdrawal of the offending agent. The rate of success is about 60% at 5 years.⁵
• Rarely the rate of recovery can be a slow process taking more than 6 months of analgesia withdrawal and support before 6 consecutive headache free days.⁷
• Some patients can be resistant to the change and concept of rebound headaches.
• Ongoing psychological support may be needed to tackle the underlying problems.
• Tapering dose of prednisolone has been successfully used to cover the first days of analgesia withdrawal to counteract withdrawal headaches.⁸
• Tricyclic antidepressants such as amitriptyline or nortriptyline, antiepileptics e.g. sodium valproate, gabapentin or topiramate, and beta blockers, for example propranolol may also be used.
• A good diet, maintaining hydration, regular exercise and simple relaxation techniques should also be advised.

• Analgesic rebound headaches are frequent, very disabling and lead to a large number of days missed from work.²
• Prolonged use of analgesics may cause a variety of side-effects, e.g. on the upper gastrointestinal tract (NSAIDs), kidneys and liver.

• Early intervention is important because the long term prognosis depends on the duration of medication overuse.
• The headache usually starts to improve within two weeks and the improvement then continues for weeks or even months.
• The patient may revert to their original headache type.