The following article is reprinted from WebMD and reviews the FDA approval of Botox for the treatment of chronic migraine.
The article is accurate but I will add some further observations and cautions.
1) We have administered 800 applications of Botox at the Headache Clinic since 1993. The total number of applications is large,but the frequency is low: this represents less than one application a week over a very long period of time. We have not had a single significant complication during that time.
2) Although I have been a critic of the FDA in many cases, I believe that the particular protocol approved by the FDA represents a significant advancement in the treatment of chronic migraine and was reviewed very thoughtfully. The FDA, in short, did a terrific job here. The specific protocol of injection sites, standard administration, and adequate total dose (200 units) is a meaningful improvement over previous protocols for Botox administration, and represents hard work by many of our colleagues in migraine research to optimize this treatment.
3) For many patients with medical problems other than migraine, we have in the past attempted to optimize the treatment of the other problems hoping to improve the chronic migraine. A common example is the patient who has significant depression as well as chronic migraine, where the use of antidepressants may benefit both depression and migraine. When depression is severe, however, it is often best to allow the treatment of depression to be optimized for that problem, rather than trying to find an antidepressant medication that would benefit both. For patients most severely affected by multiple medical problems, the FDA approval of Botox may present a significant new therapy- simpler to use, and without medication interactions, psychotropic side effects, or weight gain concerns.
4) Botox has not been shown to benefit patients with less than 15 headache days/month. This lack of benefit for episodic migraine- as opposed to chronic migraine- probably reflects the fact that patients with chronic migraine have a different disease than episodic migraine in some important ways. For the patient considering Botox, don’t overstate the number of headache days each month you are experiencing! Keep in mind that overstating the humber of headache days/month may lead to treatment with Botox that will not benefit you.
4) There is no experimental evidence that Botox cures migraine- nor is there experimental evidence there it does not. In my experience with 20 years of Botox use for migraine headache, most patients are able to stop Botox after three doses (9 months), a few stayed with treatment every three months for up to three years, but none required treatment beyond three years. Possibly the use of Botox was limited over time by cost, but my guess (and it is a guess) is that any treatment that induces a remission of chronic migraine for a sufficiently long period of time can convert a chronic migraine into a much more easily controlled episodic migraine. My experience is that the migraine characteristics return to those similar to when the headaches started man years ago; that is, from perhaps 20 days/month to three days/month, and from being refractory to all rescue medications to return of effectiveness of standard migraine medications that can be taken at the time of the headache, such as Imitrex.
5) My hypothesis of migraine progression over time involves classical conditioning. Repeated attacks of migraine “link up” with other body functions, in a manner similar to a training effect (as Pavlov described). So, over time, patients with migraine develop more and more migraine “triggers”, neck pain associated with migraine, hypervigilence and insomnia, body pain, and digestive motility disorders (“irritable bowel syndrome”). These “linked”, or classically conditioned, reflexes may be abolished, and these other health problems resolved, with suppression of migraine for a period of time. Three doses of Botox (nine months) often is sufficient.
6) A single treatment of Botox administered for chronic migraine alone is only modestly effective in reducing migraine frequency, and should be administered as part of a headache management plan that includes exercise, general health improvement, sleep regularization, restriction of environmental contributors to migraine, and possibly continued but minimized migraine preventative medication. Botox can be a significant benefit in inducing chronic migraine remission when administered by a headache specialist planning for long term improvement.
FDA Approves Botox to Treat Chronic Migraines
Injections of Botox Can Relieve Migraine Headache Symptoms for up to 3 Months
By Bill Hendrick
WebMD Health News Reviewed by Laura J. Martin, MD
Oct. 18, 2010 -- Botox -- famous for smoothing out wrinkles on the face -- has been approved by the FDA to treat chronic migraine headaches in adults.
The FDA says Botox injections have been shown to be effective in the prevention of migraines, which are debilitating headaches that cause intense pulsing or throbbing pain and affect about 12% of Americans.
“Chronic migraine is one of the most disabling forms of headache,” Russell Katz, MD, of the FDA, says in a news release. “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 headaches are sometimes called “sick headaches” because they often are accompanied by nausea and sensitivity to light and sound.
How Botox Is Used to Treat Migraines
Botox to treat chronic migraines is given at intervals of about 12 weeks as multiple injections around the head and neck to try to dull future headache symptoms, the FDA says in a statement.
The FDA says it’s important that patients who suffer chronic migraines discuss with their doctors whether Botox is appropriate for them.
Allergan Inc., the maker of Botox, says in a statement that the FDA’s approval applies to people with chronic migraine, which it defines as a “distinct and severe neurological disorder characterized by patients who have a history of migraine and suffer from headaches on 15 or more days per month with headaches lasting four hours a day or longer.”
The company says that when treating chronic migraine, qualified medical specialists administer 31 Botox injections into seven specific head and neck sites.
It says that Botox, when injected at labeled doses in recommended areas, is expected to produce results lasting up to three months depending on the individual patient.
“Chronic migraine is a debilitating but under-recognized neurological condition,” Scott Whitcup, MD, Allergan’s chief scientific officer, says in the company’s announcement. “Oftentimes, chronic migraine patients mistakenly self-diagnose their symptoms as headaches or infrequent migraine and treat them with drugs that provide rapid, but temporary, relief rather than seeking an evaluation, diagnosis and treatment from a qualified headache specialist.”
He says with the FDA’s approval of Botox to prevent migraines, there is now a new option “to reduce the days and hours spent in pain as a result of this condition.”
It says the FDA’s approval for use of Botox to fight migraines was based on the results of two studies involving 1,384 adults in North America and Europe.
The studies, published in the March 2010 issue of Cephalalgia, report that patients treated with Botox experienced a major decrease in the frequency of headache days, according to the Allergan statement.
The most common adverse reactions reported by patients being treated for chronic migraine have been neck pain and headache, the FDA says.
The FDA also has placed a “boxed warning” on the anti-migraine drug, onabotulinumtoxinA, marketed as Botox and Botox Cosmetic. The warning says the effects of the botulinum toxin may spread from the area of injection to other areas of the body, causing symptoms similar to those of botulism.
These symptoms can include swallowing and breathing problems. The FDA says it knows of no confirmed cases of the spread of the toxin effect when Botox has been used at the recommended dose to treat chronic migraines, severe underarm sweating, or conditions such as blepharospasm, an involuntary muscle spasm in the muscles surrounding the eyes.
The drug also can cause muscle weakness, double vision, blurred vision, drooping eyelids, loss of bladder control, and hoarseness, Allergan’s statement says.
The same formulation of Botox was approved by the FDA in 2002 for the treatment of facial frown lines.
The FDA says Botox does not appear to be useful in treating or preventing less frequent migraines that occur 14 days or less per month or other forms of headache