Botulinum Toxin May Reduce Migraine Frequency
Migraine patients may be glad to hear that a preliminary study suggests that botulinum injections, similar to those used to erase wrinkles from the forehead, may reduce the frequency of certain migraine headaches. Details of the study appear in the February issue of Archives of Dermatology.
Previous studies have reported inconsistent results concerning the efficacy of botulinum toxin type A (known as Botox when used for cosmetic purposes) in reducing the frequency of migraine headaches when given in doses ranging from 25 to 300 U. A new study, conducted by Christine C. Kim, MD, currently in private practice, and several colleagues, was designed to determine whether botulinum toxin type A injections given at doses used to temporarily eliminate forehead wrinkles (100 U) could effectively prevent ocular and imploding, but not exploding, migraines.
An effective treatment for migraine would be a welcome announcement for the millions of Americans who suffer with this often debilitating condition. According to the American Migraine Foundation, 36 million Americans suffer from migraine headaches, or about 12 percent of the population. Three percent of the population have chronic migraine, which means the pain is present at least 15 days each month for at least six months. Migraine is three times more common in women than men.
In the current study, Kim and her team studied 18 patients (17 women, 1 man) who had already been or were planning to be treated with botulinum injections for upper-facial wrinkles, and who also suffered with migraines. Ten patients said they had imploding (vicelike or crushing feeling) or ocular (feeling like one’s eyes are popping out) headaches, and nine reported exploding headaches (feeling like one’s head is going to explode or that pressure is building). One patient reported two different types of headache, which is why there were 18 patients but 19 data points analyzed.
Three months after each of the patients had received the botulinum injections, 13 said they had a reduction in migraine pain, including ten patients who had imploding or ocular headaches and three who had exploding headaches. Migraine frequently declined from an average of 6.8 days per month to an average of 0.7 days per month.
Migraine frequency declined from an average of 11.4 to 9.4 days per month in the patients who experienced exploding headaches, while frequency in patients who had imploding or ocular headaches declined from an average of 7.1 days to 0.6 days per month. All six of the remaining patients did not experience an improvement, and all had exploding headaches.
Botulinum toxin type A causes muscle paralysis by inhibiting the release of acetylcholine at the neuromuscular junction, but this action does not completely explain how this toxin prevents migraine headaches. Clinicians also do not have a standardized treatment approach for use of botulinum toxin type A. The results of this study show that the lower doses of the toxin used for upper-facial cosmetic purposes, which is about half the dosage used in some previous studies of migraine, appears to be sufficient to prevent imploding and ocular migraine headaches.
American Migraine Foundation
Kim CC et al. Archives of Dermatology 2010; 146(2): 159-63