Botulism Toxin
By Rear Adm. Joyce Johnson, D.O., M.A.

I always thought botulism was a poison found in home-canned foods. Can bioterrorists use it? Is it true it can treat wrinkles and nerve/muscle diseases?

When the bacteria Clostridium botulinum grows, it produces a toxin that paralyzes muscles. As a disease, botulism can occur as food poisoning, wound infection, or infant illness. About 200 cases are reported annually in the United States.

As disease or therapy, botulinum toxin binds to the nerve where it connects to the muscle, preventing the release of a neurotransmitter that tells muscles to contract. Muscle weakness or paralysis results. In large or uncontrolled doses, this is dangerous. Botulism is considered a potential bioterrorist threat because of its potent neurotoxic capabilities. But when the bacteria is injected in minute amounts into muscles that contract too much, its nerve-paralyzing (and resulting muscle-relaxing) properties can have positive therapeutic effects.

When home-canned products are not adequately heated, C. botulinum spores can survive. They grow best in low-acid foods, producing the toxin over a period of months or years. One to four days after tainted food is eaten, initial symptoms, including nausea, vomiting, and diarrhea, begin. Weakness and paralysis follow.

C. botulinum is commonly found in soil and can invade the body through breaks in the skin. Over time, as the bacteria grow, they produce toxin in the wound, with many of the same paralytic symptoms as food botulism. Wound botulism might not become apparent until a couple weeks after the initial infection. 

Among the ways infants can get botulism is by ingesting C. botulinum spores found in honey. The spores grow in the intestine and produce toxin. The first symptom is constipation from intestinal paralysis, followed by generalized weakness and paralysis. For this reason, honey is not recommended for infants and toddlers.

Botulinum toxin has received Food and Drug Administration (FDA) approval in the treatment of blepharospasm (eyelid spasms), restrictive strabismus (a specific type of “crossed eyes”), and cervical dystonia (a painful spasm of the neck muscles). The toxin is injected into the nerves of the affected area and relaxes the muscles. Injections are repeated every three to six months.

In 2002, the FDA approved botulinum toxin injections for glabellar lines (forehead wrinkles). Although not specifically FDA-approved, the toxin often is injected into other areas to treat wrinkles. At least 2 million botulinum toxin treatments are expected to be performed in 2003.