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Botox

Botox has been in the news recently as a quick and easy way to reduce wrinkles in the face. The name Botox is short for botulinum toxin, which is the same substance that causes a type of food poisoning called botulism. This toxin is extremely deadly to humans, but has also been shown to provide health benefits in very dilute doses. How can one substance affect the body in such different ways? How safe is the cosmetic use of Botox?

The toxin is derived from the bacteria Clostridium botulinum, which exists as a spore. The spore must be allowed to germinate in order to produce the toxin. Once in the body, the toxin inhibits the release of acetylcholine at the synapses of motor nerves. This prevents muscles from contracting. Death results when paralysis of the diaphragm and chest muscles causes lung failure.

Unintentional Exposure

The most common way in which humans are exposed to harmful doses of botulinum toxin is through contaminated food. The necessary conditions for the clostridium botulinum spore to germinate and produce the toxin are an anaerobic environment of high pH. Therefore, low-acid canned foods like soup and vegetables are most susceptible to the toxin. While the spore itself is heat resistant, the toxin produced by the spore is heat labile and becomes deactivated at temperatures above 85 degrees Fahrenheit. This is one of the reasons that it is recommended that you properly cook all food.

A less common method of exposure occurs when spores come in contact with a wound on the skin. This is seen most often in heroin addicts who use needles to inject the drug. Since the spore is heat-resistant, even drug users who heat the drug prior to injection may still become infected.

Potential Biological Weapon

Botulinum toxin is impractical as a biological weapon due to the fact that it cannot be absorbed through skin and, unlike anthrax, it is difficult to be inhaled. But what makes botulimun toxin appealing as a biological weapon is its potency. A single gram of the toxin is enough to kill a million people. In the 1991 Gulf war, Iraq was reported to have possessed 19,000 liters of concentrated botulinum toxin. This is enough to kill the entire human population three times over.

Medical and Cosmetic Uses

The FDA approved botulinum toxin type A for cosmetic use in 2002 and, consequently, millions of people have seen the signs of aging reduced in their faces. Dilute doses of the toxin are effective for medical uses because they cause only localized muscle relaxation as opposed to total muscle paralysis. Dilute botulinum toxin not only relaxes the face muscles that cause wrinkles, but it has also been used to prevent muscle spasms in stroke patients and relax the head and neck muscles that cause migraines. Overactive bladder can also be treated with dilute doses of botulinum toxin.

Copyright 2006, John Wiley & Sons Publishers, Inc.