Botulinum Toxin Facts

One of the most acutely toxic poisons known to mankind, botulinum toxin is extremely lethal to humans. One microgram of it can kill by causing paralysis in the musculoskeletal and respiratory systems. The paralysis is caused by blocking the release of the chemical neurotransmitter acetylcholine. The lack of acetylcholine prevents nerve impulses from reaching muscles, rendering them immobile and uncontrollable.

Botulinus intoxication, the paralytic disease also known as botulism, is caused by botulinum toxin. The anaerobic, Gram positive, spore-forming bacteria called Clostridium botulinum produces it. Infant botulism or intestinal botulism, caused by the ingestion of Clostridium botulinum spores, is one of the kinds of botulism. Another kind, wound botulism, is caused when Clostridium botulinum infects a wound. Food-borne botulism is the third kind of botulism, caused by eating food that contains botulinum toxin.

Babies less than 12 months of age are susceptible to infant botulism because their digestive juices are less acidic than those of adults and older children. Thus, they have less capacity to destroy Clostridium botulinum spores that have been ingested. The spores germinate in the infant's intestines and produce botulinum toxin. Constipation, followed by generalized weakness, loss of head control and difficulty feeding are the symptoms of infant botulism.

4 to 14 days after a wound is infected by Clostridium botulinum, the symptoms of wound botulism, such as difficulty in swallowing, weakness of the muscles, drooping of the eyelids, difficulty in breathing, double or blurred vision, slurred speech, incontinence, diarrhoea, and dryness of the mouth begin to appear. The symptoms of food-borne botulism are the same but appear sooner, about 12 to 38 hours after eating food containing botulinum toxin.

Botulism can be treated with the use of botulinum antitoxin. Two primary types of antitoxin are available. One of these is trivalent botulinum antitoxin and the other is heptavalent botulinum antitoxin. The administration of antitoxin, coupled with artificial ventilation (as a measure to combat the effect of respiratory paralysis caused by the toxin) until botulinum toxin is completely excreted or metabolised, is effective if treatments are initiated on time.

The Clostridium botulinum spores which produce botulinum toxin are heat resistant and can survive even prolonged boiling at 100 degrees Celsius. Thus, proper handling of food to prevent contamination by Clostridium botulinum bacteria is important. The growth of Clostridium botulinum can be prevented by low pH levels, high salt concentration, and refrigeration. Botulinum toxin itself is readily destroyed by thorough cooking.

Despite the toxicity of botulinum toxin, one of its serologically distinct types, namely, botulinum toxin type A, is used in the treatment of facial lines and wrinkles, certain neurological disorders, and hyperhidrosis. Botox, Dysport, Myobloc, Neurobloc and Xeomin are the brand names under which it is marketed for the treatment of neurological conditions. For cosmetic treatment purposes, it is commercially available under the trade names Botox Cosmetic and Vistabel.

There is an indication that botulinum toxin can help promote weight loss by speeding up gastric emptying time. There is also an indication that it is effective in the treatment and prevention of chronic headaches, as well as chronic musculoskeletal pain, by blocking nerve impulses to the muscles of the affected area.