Botox injections may not be an effective treatment for migraines as previously thought, says a new study published Tuesday (February 8) in the journal Drug and Therapeutics Bulletin.
An earlier study indicated that botulinum toxin A, sold under the name Botox and marketed primarily for cosmetic use to paralyze muscles that cause wrinkles, could be used to help migraine sufferers.
Some countries, including Britain and the U.S, approved Botox for use as a migraine treatment after a trial of more than 1,300 patients indicated it was successful in reducing the frequency of headaches.
After contacting individuals used in the clinical trials, the study authors say they found "limited evidence of benefit," and that nearly two-thirds of the participants had actually been overusing headache treatments .
In about 10 percent of the cases, Botox actually led to worsening migraine symptoms, and another 10 percent of the participants suffered from itching rash, pain, stiffness and muscle spasms due to the drug.
"These discrepancies and the limited evidence of benefit make it difficult for us to see a place for botulinum toxin A as treatment for chronic migraine," concluded the study authors.