Botulinum toxin (Botox)-famous for smoothing out wrinkles on the face-has been approved by the FDA to treat chronic migraine in adults. The FDA says Botox injections have been shown to be effective in the prevention of migraines which are debilitating headaches that causes intense pulsating or throbbing pain and affect about 12% of population.
Chronic migraine is one of the most disabling forms of headache, “Patients with chronic migraine experience a headache more than 14 days of the month. This condition can greatly affect family, work, and social life, so it is important to have a variety of effective treatment options available.
Migraine is the commonest cause of headache, affecting about 10-15% of women and 5-8% of men. In many cases, migraine becomes chronic and leads to frequent headaches. Oral preventive therapies for migraine are available, but are ineffective in some and lead to adverse events in others. In these patients, botox therapy has a great role to play. Botox is injected in scalp and neck muscles (frontalis, temporalis, occipitalis, cervical, trapezius, etc) using a very thin needle. The procedure can be done in the office, with little discomfort to the patient, and is completed within 15-20 minutes.
What is botulinum toxin? Botulinum toxin is produced by bacterium, Clostridium botulinum. Seven different subtypes of botulinum toxin (A-G) are known. A highly dilute preparation of botulinum toxin type A (Botox) was introduced in clinical practice in the 1970s and 1980s to treat squint and blepharospasm. Since then it has found uses in other areas of neurology including hemifacial spasm, writer’s cramp, cervical dystonia, post-stroke spasticity.
Botulinum toxin and headache In the mid-1990s a number of people reported improvement in headaches in patients receiving botulinum toxin for other reasons. Well-conducted clinical trials of botulinum toxin in various types of headache followed. Detailed analysis of the results suggested, however, that there might be a subgroup of patients with chronic migraine who could benefit, and further trials were undertaken.
Botox® in chronic migraine: the PREEMPT trials Two Phase 3 Research Evaluating Migraine Prophylaxis Therapy (PREEMPT) trials recruited 1384 patients with chronic migraine, and randomised them to treatment with Botox® or placebo. These patients were suffering on average 20 days of headache each month, of which 18 were moderate or severe. Those randomised to Botox® received fixed-site, fixed dose injections every 12 weeks over 56 weeks. These injections covered seven specific areas of the head and neck, with a total dose of between 155-195 units. At six months, after two cycles of treatment, those treated with Botox® had on average eight less days of headache each month. After 12 months, 70% of those treated had ≤50% the number of headaches that they had done originally.
How does botulinum toxin work in chronic migraine? Unlike many of the other conditions in which it is used, it is not thought to work by relaxing overactive muscles. Botulinum toxin has been shown to reduce pain in a number of disease states, including cervical dystonia, neuropathic pain, lower back pain, spasticity, myofascial pain, and bladder pain. Botulinum toxin is believed to inhibit the release of peripheral nociceptive neurotransmitters, which may then have a knock-on effect on the central pain processing systems that generate migraine headaches.
Is Botox® right for me? Only patients with chronic migraine are eligible for treatment with Botox®. Chronic migraine is defined as headaches occurring on 15 or more days each month, at least half of which have migrainous features.
In general, all botox injection therapies are done on an out-patient basis. Patients can come after eating (fasting is not necessary). It is done without any anaesthesia, in the office setting. The entire procedure is completed in less than 30 minutes and patients are free to return home immediately after the procedure. No leave from work is required and they can join work the next day.
Neurology deptt metro hospital is running dedicated botox clinic for treating disorders like chronic migraine, hemifacial spasm, blepharospasm, post stroke spasticity, cervical dystonia, cerebral palsy & writer cramp.