More and more headache patients are hearing about BOTOX and are requesting information as to its potential use for treating their headaches. In an attempt to provide a balanced perspective (and to avoid saying the same thing over and over and over…) I prepared this information sheet.
“BOTOX” is short for “botulinum toxin,” a protein produced by a bacterium (clostridium botulinum) that in high doses can cause diffuse muscular paralysis, inability to breathe, and death. Injected into specific muscles in tiny doses, however, BOTOX has been demonstrated to be effective in treating various types of involuntary muscle contraction safely and effectively. BOTOX also is used for cosmetic purposes, relaxing facial muscles and so smoothing out facial wrinkles.
While evaluating BOTOX administered for disorders involving muscle contraction, investigators discovered that the pain experienced by patients with those disorders tended to improve even before any meaningful reduction in muscle contraction occurred. In addition, patients with migraine who were receiving BOTOX for cosmetic purposes in many instances reported a significant improvement in their headaches following the injections. These observations subsequently led to a series of clinical research studies designed to assess the value of BOTOX therapy for headache prevention, and to make a long story short, the results from these studies have been mixed; BOTOX does not appear to be effective in treating tension type headache or patients with relatively infrequent migraine attacks. Regardless, a substantial number of headache experts continue to feel that BOTOX may be of value in treating chronic migraine. Generally, they recommend that its use be restricted to patients who fail to respond to conventional preventative therapy or experience intolerable side effects from such therapy. Because BOTOX is not FDA-approved for migraine treatment, many insurance carriers categorize its use in that setting as experimental and will not provide reimbursement.
There is currently a multicenter national trial (PREEMPT) in progress examining the safety and effectiveness of BOTOX administered for the treatment of chronic migraine (“chronic” implying the patient is experiencing at least 15 days of headache per month). In that study, as many as 195 units of BOTOX are injected into 40 or more sites located over the forehead, temples, back of the head, neck, and shoulders. The entire procedure requires only 5 to 10 minutes, and most patients find it to be mildly uncomfortable at worst.
When BOTOX is administered for migraine therapy, side effects are rare. The most common side effects are bruising or swelling at the injection sites or transient headache of mild intensity that resolves within 24 to 48 hours. On rare occasions patients have developed flu-like symptoms that typically resolve within a day to two. Many centers have reported transient eyelid droop as a side effect. BOTOX will cause paralysis of the muscles into which it is injected, and patients may note associated smoothing of forehead wrinkles and some difficulty in voluntarily lifting the eyebrows; when present, these effects tend to vanish within 3 to 4 months.
In patients whose headaches appear to diminish following BOTOX injections, the clinical improvement may not be apparent for 1 to 2 weeks following 345 346 February 2007 the procedure. With the initial treatment any improvement that occurs tends to persist for a time ranging anywhere from 2 weeks to 2 months or more. With subsequent treatment, some patients have reported that the improvement in headache may be more prominent and longer in duration, persisting for up to 3 or 4 months.
Injection of BOTOX for migraine prevention is a short, simple procedure that is performed in the clinic, and it is extremely unusual for a patient to suffer any significant side effects following treatment; patients typically are able to drive and otherwise function normally immediately after the injections. Because its effects on a developing fetus are unknown, women who are pregnant should not receive BOTOX.
In summary, BOTOX appears to be safe when administered for headache treatment, but its effectiveness in treating chronic migraine remains to be proven.
John F. Rothrock, MD