Medication overuse headache usually develops in people who have migraines or a tension-type headache.
The type of headache pain varies from person to person.
Doctors diagnose medication overuse headaches based on how often people take headache drugs and have headaches.
Doctors treat these headaches by stopping the headache drug, by prescribing a different type of headache drug to manage symptoms caused by stopping the drug, and often by prescribing drugs to treat the original headache disorder.
(See also Overview of Headache.)
Medication overuse headache occurs 1 to 2% of the general population. It is more common among women than men.
Most people with this type of headache are taking headache drugs for migraines or tension-type headaches, They are taking too much of the drug or taking it too often, usually because the drug is not effectively relieving their pain.
The most common causes of medication overuse headache are overuse of the following:
However, overuse of other nonsteroidal anti-inflammatory drugs (NSAIDs), ergotamine, and triptans (used to treat cluster headaches and migraines) can also cause this disorder.
What causes medication overuse headache is poorly understood. However, people with this type of headache may have an overly sensitive nervous system. That is, the nerve cells in the brain that trigger pain are too easily stimulated.
Substance dependence is more common among people with medication overuse headaches. They may also have a genetic predisposition to develop medication overuse headache.
Doctors base the diagnosis of medication overuse headache on how often people who are regularly taking headache drugs have headaches and on how often people take the headache drugs.
Medication overuse headache is diagnosed when all of the following are present:
How many days a month a drug indicates overuse depends on the drug:
Rarely, computed tomography (CT) or magnetic resonance imaging (MRI) is done to exclude other disorders.
People are counseled to avoid using previously overused drugs. They are also taught and encouraged to adopt healthy lifestyle habits.
Usually, the overused drug is stopped abruptly. However, in people who are taking high doses of opioids, barbiturates, or benzodiazepines, the amount of the overused drug is gradually decreased, over 2 to 4 weeks. Stopping these drugs more abruptly can cause symptoms such as nausea, restlessness, anxiety, and poor sleep. Stopping any kind of pain reliever can cause headaches to occur more often, last longer, and become more intense. Symptoms after stopping a drug may last a few days or up to 4 weeks.
A rescue drug is used to treat headaches that occur after stopping the overused drug. A different type of headache drug is used if possible. Doctors limit use of rescue drugs to less than twice a week if possible.
Preventive drug treatment for the original headache is started before or after the overused drug is stopped.
If rescue and preventive drug treatments seem unlikely to be effective at relieving symptoms, other drugs (called transitional or bridging drugs) can be given. Transitional drugs (see table Some Drugs Used to Treat Migraines) include
After medication overuse disorder has been treated, people are instructed to limit their use of all headache drugs used to stop (abort) headaches as follows:
Drugs used to prevent headaches should be continued as prescribed.
Doctors encourage people to keep a headache diary. In it, people write down the number and timing of attacks, possible triggers, and their response to treatment. With this information, triggers may be identified and eliminated when possible. Then, people can participate in their treatment by avoiding triggers, and doctors can better plan and adjust treatment.