Botox, More Than a Wrinkle Eraser
Botox®, the neurotoxin that is best known for its ability to temporarily erase wrinkles and frown lines, was approved by the Food and Drug Administration (FDA) for medical purposes more than a decade before it was approved for cosmetic reasons (Botox® Cosmetic). Since Botox was first approved as a treatment for several eye conditions in 1989, it has been used to treat a wide variety of medical conditions ranging from excessive sweating to migraine, cerebral palsy, postsurgical pain, bladder spasms, and dystonia.
The recent death of Kristen Spears, whose family says the seven-year-old died as the result of an overdose of Botox that she received to treat her cerebral palsy, has lifted the neurotoxin into the spotlight once again. This controversial drug uses a powerful poison called botulinum toxin, which is derived from the bacterium Clostridium botulinum. It is a nerve blocker that binds to the nerves that lead to the muscles and prevents the release of a neurotransmitter called acetylcholine, which activates muscle contractions. When the signals are blocked, muscle spasms are reduced significantly.
Medical Uses of Botox
Botulinum toxin has been studied for decades for its therapeutic properties, and it has been used to treat patients for various conditions for 20 years in 80 countries. In the United States, Botox has been FDA approved for a limited number of conditions, although the drug can be legally prescribed by doctors for additional medical uses as well (off-label use), including cerebral palsy.
In the 1950s, scientists first discovered that the active ingredient in Botox could relieve muscle spasms. Several decades of research ensued, and in 1989, the FDA approved botulinum toxin to treat blepharospasm (eyelid spasms) and strabismus (crossed eyes or lazy eye) in adults. Blepharospasm is an abnormal, involuntary blinking or spasms of the eyelid. Most people develop the condition without any warning symptoms, and may also experience sensitivity to light, fatigue, and emotional tension. Botox provides improvement in about 15 percent of cases.
People with strabismus experience double vision, loss of depth perception, eye fatigue, reading difficulty, and blurry vision. Treatment with Botox can relax the muscles for several months and may even permanently cause a change in eye alignment. Botox is not indicated for treatment of strabismus in children.
Botox was then approved by the FDA in 2000 for treatment of cervical dystonia. This condition, also known as spasmodic torticollis, is characterized by involuntary contracting of the neck muscles and sometimes the shoulders, which causes abnormal movements and awkward posture of the head and neck. It is associated with considerable pain and discomfort, and can severely limit an individual’s ability to perform everyday tasks, such as eating, getting dressed, or driving.
In 2002, Botox Cosmetic was approved for reduction of frown lines, and a drug that was formerly relatively unknown by the general public reached star status. In 2004, individuals who suffer with excessive underarm sweating that does not respond to topical medications had a new FDA-approved treatment option when Botox was approved for axillary hyperhydrosis. The excessive sweating is caused by over stimulation of the sweat glands in the autonomic system, and Botox inhibits the activity of the nerves responsible.
In addition to FDA-approved uses for Botox, the drug is also sometimes prescribed for treatment of migraine, chronic pelvic pain, overactive bladder, pain following mastectomy, and tinnitus. A recent article published in the Expert Opinion on Biological Therapy reviewed clinical trials that used Botox in a variety of migraine patients, for example, found that the neurotoxin produced mixed results but has provided good relief for some patients.
In the case of postsurgical mastectomy pain, Julio Hockberg, MD, professor and chief of plastic and reconstructive surgery at West Virginia University, found that women who received Botox injections for pain control required 89 percent less morphine during the first 24 hours after surgery and had shorter hospital stays. Other general surgeons also sometimes use Botox for pain management following surgery.
Adverse Effects of Botox
Use of Botox can result in life-threatening side effects, and symptoms can occur hour to weeks after receiving an injection of Botox. Problems swallowing, speaking, or breathing can happen and even result in death. People who have these difficulties before receiving Botox are at greatest risk of experiencing these problems after injection. The effect of botulinum toxin may spread away from the injection site and cause botulism, which is characterized by muscle weakness all over the body, double vision, hoarseness, loss of bladder control, and trouble breathing and swallowing.
Other side effects of Botox may include dry mouth, pain or discomfort at the injection site, tiredness, neck pain, headache, and eye problems, such as double vision, blurry vision, drooping eyelids, swelling of the eyelids, and dry eyes.
Although Botox is still best known for its role in temporarily erasing wrinkles, it also has medical uses that can significantly improve the lives of many people who suffer with painful and/or life-altering conditions. Research into the medical uses of Botox continues.
Cady RK. Expert Opinion on Biological Therapy 2010 Feb; 10(2): 289-98
Dystonia Medical Research Foundation
Layeeque R et al. Annals of Surgery 2004 Oct; 240(4): 608-13
National Eye Institute