Medication Overuse Culprit in Chronic Migraines

From the Diamond Headache Clinic Research and Educational Foundation

ORLANDO?A 52-year-old woman with a history of migraine for most of her life had recently been having more and more headache episodes and was taking an increasing number of analgesics, but she had not enjoyed a headache-free day in 4 years. "Her background headache was like a chronic tension-type headache, but daily she would get these severe headaches, an exacerbation that looked like migraine, a one-sided headache that was severe and pounding, with nausea and vomiting and heightened sound sensitivity."

Thomas N. Ward, MD, professor of medicine, Dartmouth Medical School, Hanover, NH, told this story at a recent Headache Update 2006 seminar.

The woman spent so much time in the emergency department that she lost her job. At that point she was admitted to the hospital.

"We treated her with intravenous medication. We put her on longer-acting medications that were less likely to cause rebound. And in the course of the next several weeks, while she was in the hospital, she became headache free," Dr Ward told IMWR.

"During the next 3 months or so, instead of daily headache, she had a total of 3 migraines," he said.

Chronic daily headache is defined as headache occurring ≥15 days a month. The headaches do not have to be constant or occur every day. The causes are myriad:

? Primary headaches can be caused by something else, such as chronic tension-type headache, or chronic migraine, or even cluster headaches.

? Secondary headaches can also cause chronic daily headache. These potentially ominous headaches can sometimes be signs of an underlying condition, such as thyroid disorders (eg, hyperthyroidism or hypothyroidism) or a centeral nervous system infection (eg, Lyme disease).

? Chronic daily headaches can also be caused by structural abnormalities in the brain, such as a tumor or an abnormal collection of blood vessels, called arteriovenous malformation.

Accurate diagnosis depends on getting as much information as possible from the patient during the history taking.

A full neurologic exam and judicious testing, usually accompanied by neuroimaging, blood tests, and sometimes a look at spinal fluid pressure may be needed to determine the cause. But this cannot be done in 10 minutes.

Appropriate assessment might have spared our woman all her pain. "I spent the better part of an hour and a half getting the history, examining the patient, making a treatment plan. I certainly could not have done it in 10 minutes, which is the first problem. The second problem is, while she was overusing over-the-counter medication (butalbital), she need not have been doing that. Something as simple as Tylenol, or medications that have Tylenol and caffeine in them, can cause rebound?these things can perpetuate chronic daily headache."

The watchword for chronic migraine treatment is "less is more," Dr Ward says. Patients with acute migraines should not take short-acting medications on more than 2 to 3 days a week. If this does not relieve the pain, preventive medication may be needed to avoid analgesic rebound from medication overuse.

Key points

A thorough headache evaluation cannot be done in a few minutes.

Overuse of Tylenol, or drugs containing Tylenol and caffeine, can cause headache rebound.

Remember the adage, "less is more," and limit the treatment of acute migraines to short-acting agents up to 2-3 days/wk.