Botox, most commonly used to reduce fine lines on adult foreheads, has now been shown to alleviate the pain of chronic headaches in adolescents. Although a treatment of last resort, adolescents attending the Pediatric Headache Clinic at The Hospital for Sick Children (SickKids) may get the toxic injections, spending the next few months headache-free.
"These kids have a headache everyday of their lives. Many have been through a lot," says Dr. Daune McGregor, staff neurologist, of the patients that come to Toronto's downtown clinic. By the time they reach the door, they have endured many other treatments, such as medications, behaviour modification, and acupuncture. "They have also had MRI imaging to rule out tumours. Chronic headache is a diagnosis of exclusion.�
Most kids with chronic daily headache actually have a form of migraine. "They probably have a genetic predisposition," says McGregor, adding, "headaches are also influenced by stress, eating habits, and dehydration."
Botox is the commercial name for the bacterium Clostridium botulinum toxin type A, which was first used for headaches after plastic surgeons reported a decrease in migraines following cosmetic injections. How Botox works is not fully understood. However, it is believed to inhibit pain pathways in the brain by shutting down neurotransmitters that communicate with nerve endings. This inhibition effects the perception of pain, causes muscle relaxation, and produces temporary paralysis.
"There are standard patterns for injections across the forehead, which go into the scalp and not the brain," explains McGregor. The injection sites, of which there can be up to 60, are also dependent on an individual�s pain pattern. Treatments are given every three to four months; the time it takes nerve endings to build new connections and for muscle function to be restored.
Eliminating the need for other treatments
"About 70% of teens treated see some improvement and continue their treatments," reports McGregor, whose patients at the clinic are part of a study evaluating the treatment. In addition to a reported decrease in pain, many partipants, 11 to 17 years old, noted more frequent and longer headache-free periods and an improvement in quality of life. For at least some of these 20 adolescents, other existing treatments, including the use of pain relieving drugs, are continued in addition to Botox. The hope is that Botox will reduce the need for daily medications. Results of the study will be published in late 2009.
Botox is not yet approved for the use of headaches or migraines in children, though the practice is not uncommon for adults in Canada. Adults experience few and mostly mild side effects, including muscle weakness, neck and shoulder pain, injection site hemorrhage, and damage to muscles that controls the eyebrows.
The implications of long-term Botox treatment, both positive and negative, are still being explored. "Some patients get very dependent on it and might be doing this for life," says McGregor. And while this may be better than the alternative of a daily migraine, "ideally, the goal is to break the cycle so that treatment is no longer necessary."