Botulinum Toxin A Injections Possible Treatment for Refractory Headache Syndrome

February 21, 2007 (New Orleans) — A new study suggests that botulinum toxin A (Botox, Allergan) may be helpful in treating refractory headache syndrome (RHS). A retrospective review of patients receiving this treatment showed a reduction in the number and duration of headaches in patients with chronic migraines, daily headaches, and cervicalgia headaches who had failed conventional treatment.

In RHS, patients continue to experience severe symptoms even after being treated with combinations of different therapies, including trigger-point injections and medications such as antidepressants, calcium-channel blockers, beta blockers, triptans, and antiepileptics.

Andrew Linn, MD, chief anesthesiology resident at Beth Israel Deaconess Medical Center in Boston, Massachusetts, said, "Botox has become popular for RHS patients, often as a treatment of last resort." These findings suggest it may be a viable treatment option.

Their findings were reported here at the American Academy of Pain Medicine 23rd Annual Meeting.

Retrospective Review

Dr. Linn and colleagues undertook this review to determine whether the use of botulinum toxin influences the number of headaches occurring per week or the average duration of those headaches in such patients. The study consisted of a chart review of 105 patients who received botulinum toxin for RHS between 1999 and 2005 at the Arnold Pain Management Center, a tertiary pain clinic at Beth Israel Deaconess Medical Center.

Pain was reported by the patients using the visual analog scale (VAS) (0 – 10). A positive response to therapy was defined as at least a 30% reduction in each of the following, after 4 to 6 weeks following treatment: VAS score, the number of headaches experienced per week (HPW), and/or the same percentage decrease in the hours (duration) per headache episode (HHrs). Sex, age, total dose of botulinum toxin per session, injection sites, and other current therapies were noted for each patient.

Of the 105 patients, 44 (42%) reported a decrease of at least 30% in their VAS scores; 36 (34%) reported a decrease of at least 30% in the number of HPW; 14 patients (13%) experienced a decrease of at least 30% in the number of HHrs per week; 9 patients (9%) experienced a decrease in both HPW and HHrs.

In the study, 99 patients (94%) were receiving concurrent trigger-point injections. Dr. Linn commented, "Most of these patients came in already using several drugs for their headaches. For the most part, they just continued the drugs while on the Botox." All patients were taking at least 2 medications, including antidepressants, antiepileptics, opioids, triptans, calcium-channel blockers, beta blockers, nonsteroidal anti-inflammatory drugs, and acetaminophen.

Dr. Frederick Burgess, an anesthesiologist and pharmacologist at Rhode Island Hospital, in Providence, commented, "This study indicates possibilities for using Botox as a 'rescue drug' to 'salvage' patients who have tried other therapies for these headaches without success. It's not a clean study — there have been cases in which using saline for trigger-point injections have also worked. So further well-controlled trials are needed for Botox injections."

American Academy of Pain Medicine 23rd Annual Meeting: Abstract 127. Presented February 8, 2007.

Medscape Medical News © 2007  Medscape

Cite this: Lexa W Lee. Botulinum Toxin A Injections Possible Treatment for Refractory Headache Syndrome - Medscape - Feb 21, 2007.