Drugs Can Sometimes Prevent Migraines, at a Cost
Study finds many have side effects so bothersome that sufferers stop taking them
By Barbara Bronson Gray
MONDAY, April 29 (HealthDay News) -- People with severe or frequent migraines often turn to drugs to prevent them. But do the medications work?
A new review of preventive treatments shows there is not much difference in the effectiveness of commonly prescribed drugs -- they work for some people, in some cases. But there is wide variation in the amount and severity of side effects associated with the drugs.
The researchers found that drugs worked better than inactive placebos in reducing monthly migraine attacks. They prevented half or more migraines in 200 to 400 people per 1,000 treated. But many of the medications had side effects so bothersome that sufferers frequently stopped taking them.
That could be because none of the drugs used to prevent migraines was designed specifically for that purpose, explained Dr. Jason Rosenberg, director of the Johns Hopkins Headache Center. "So, it's not surprising that they don't work all that well. Only one-third get halfway better, according to the study, so a doctor has to treat three people to get one patient better."
Rosenberg, who was not involved with the study, suffers from migraines and thinks many primary care doctors may be less aware of the side effects of the drugs used to prevent migraines than are headache specialists. So, they may not warn patients about the potential problems and frequently don't follow up to see how the patients are doing, he added.
The side effects are typically no fun, said Rosenberg. "A number are badly tolerated. Some cause weight gain, hair loss, can cause birth defects [one drug], some tingling, sleepiness, impaired ability to exercise, an increased risk of diabetes and sexual side effects," he noted. Some problems, such as kidney stones, are only detected with long-term follow-up, he added.
That's why physicians and patients need better information, said review author Dr. Tatyana Shamliyan, a researcher at the Minnesota Evidence-Based Practice Center in Minneapolis. Good research clearly shows potential benefits and harms, and "helps a great deal in making informed decisions," she said.
But finding information about the options and downsides can be difficult.
Rosenberg said that before Shamliyan's study, no one had done a thorough, comprehensive review of the side effects of medications used to prevent migraines. "They've done a Herculean task," he said.
Both the American Academy of Neurology and the American Headache Society have issued guidelines that recommend two types of anti-epileptic drugs and two beta blockers for prevention of migraines in adults. But neither medical group considered the value of balancing the effectiveness against the side effects, Shamliyan said.
Migraines affect about 12 percent of the U.S. population, and involve throbbing or pulsing head pain, often associated with sensitivity to light and sound, according to the U.S. National Library of Medicine.