A study published in the April 25 issue of JAMA reveals that individuals suffering from chronic migraine headaches and chronic daily headaches may receive a small to modest benefit using botulinum toxin A ("Botox") injections. However, the researchers found botox did not provide greater benefit than placebo for preventing episodic migraine or chronic tension-type headaches.
The U.S. Food and Drug Administration approved botox for preventive treatment for chronic migraines.
The researchers explained:
"Migraine and tension-type headaches are common. Although up to 42 percent of adults experience tension-type headaches sometime in their life, most do not seek medical advice.
Migraines are less common, with a worldwide prevalence between 8 to 19%, but as associated with greater disability. Migraine headaches are responsible for $1 billion in medical costs and $16 billion in lost productivity per year in the United States alone."
Clinicians first observed that patients with chronic headaches experienced an improvement after receiving cosmetic botulinum toxin A injections. This resulted in various studies suggesting that botox injections were beneficial for patients with headaches. However, medical literature on botulinum efficacy for headaches has been mixed.
In order to determine whether botox is effective as preventative treatment of migraine, tension, or chronic daily headaches in adults, Jeffrey L. Jackson, M.D., M.P.H., of the Medical College of Wisconsin, Milwaukee, and his team examined 27 randomized placebo-controlled trials that included 5,313 individuals, as well as 4 randomized comparisons with other medications.
The researchers categorized headaches as:
- Episodic - less than 15 headaches per month
- Chronic- (15+ headaches per month) migraine and episodic or chronic daily or tension headaches
However, they found no considerable association between the use of botox and reduction in the number of chronic tension-type headaches (675, -1.43 headaches per month) or episodic migraine (1,838 patients, 0.05 headaches per month).
Compared with placebo, the researchers found that botox was linked to:
- Skin tightness
- Neck stiffness
- Neck pain
- Muscle weakness
- Paresthesias (a prickly, tingling sensation)
- Greater frequency of blepharoptosis (drooping of the upper eyelid)
The researchers explained:
"Botulinum toxin A was not associated with a reduction in headache frequency vs. valproate in a study of patients with chronic and episodic migraines (0.84 headaches per month) or in a study of patients with episodic migraines (0.3 headaches per month).
Botulinum toxin A was associated with a greater reduction in average headache severity than methylprednisolone in a single trial among patients experiencing chronic tension-type headaches (-2.5 headaches per month)."
"Our analyses suggest that botulinum toxin A may be associated with improvement in the frequency of chronic migraine and chronic daily headaches, but not with improvement in the frequency of episodic migraine, chronic tension-type headaches, or episodic tension-type headaches.
However, the association of botulinum toxin A with clinical benefit was small. Botulinum toxin A was associated with a reduction in the number of headaches per month from 19.5 to 17.2 for chronic migraine and from 17.5 to 15.4 for chronic daily headaches."
Written By Grace Rattue