DEAR DOCTOR K:
I thought Botox was just a wrinkle remedy. But a friend told me she uses it to treat overactive bladder. Then someone else said he had a Botox injection for tennis elbow. What exactly is Botox? What else does it treat?
It’s true, Botox’s applications are more than skin-deep. Botox is one brand of botulinum toxin A. This is a substance made by the bacteria responsible for botulism, a foodborne illness that causes paralysis and sometimes death. When purified and diluted, however, botulinum toxin is a safe and useful drug.
Botulinum toxin is a muscle relaxant. In 1989 the FDA approved it for treating crossed eyes. Next came approval for smoothing facial lines, or wrinkles. Since then, Botox and newer brands of botulinum toxin have been used to treat a growing number of conditions.
Some conditions that injections of botulinum toxin are currently used for include:
- Overactive bladder and urge incontinence. Botox reduces episodes of incontinence in people for whom incontinence drugs taken by mouth don’t work.
- Chronic migraine headache. Botox is approved for treating people with severe, frequent migraines. It doesn’t prevent migraines. But it may reduce their number and duration.
- Upper limb spasticity. Elbows, wrists or fingers often contract uncontrollably as a result of cerebral palsy, multiple sclerosis, stroke, brain trauma or spinal cord injury. Botox may relax muscles enough to allow people to perform basic activities like washing and dressing.
- Cervical dystonia. Uncontrollable contractions in neck muscles can force the head into awkward and uncomfortable positions. Botulinum toxin is approved for treating cervical dystonia. It relaxes the neck muscles enough to return the head to a more normal position.
- Excessive underarm perspiration. When even the strongest antiperspirants don’t work, Botox can lessen heavy sweating. It does so by blocking the nerve signals that stimulate sweat glands.
- Blepharospasm. Botulinum toxin may treat uncontrolled contractions of eyelid muscles that cause rapid blinking and may even clamp the eyes shut.
- Spasmodic dysphonia. This unusual disorder affects about 50,000 people in the U.S. Its cause is unknown. They have trouble speaking smoothly. The words come out in a hesitant and sometimes explosive fashion. Well-known radio commentator Diane Rehm has made public the fact that she suffers from this condition — and has continued her remarkable career with proper treatment.
Once a drug is approved by the FDA, doctors can prescribe it for almost any purpose. This is called “off-label” use. Botulinum toxin is used off label to treat conditions as varied as teeth grinding, tennis elbow and pelvic pain.
It is remarkable that a toxin first known because of the terrible illness it causes, botulism, actually can be an effective treatment for many conditions — if used properly. That’s because of research directed at finding out what caused botulism. When the role of the toxin was understood, scientists also had an important insight: While too much of a bad thing can be awful, a little bit of a bad thing sometimes can be therapeutic.