Botulinum toxin is a protein that helps stop muscle spasms when it is injected directly into the muscle. Muscle spasms are caused by chemical messages sent to the muscles from nerves. These messages tell the muscles to contract (to tighten up). Botulinum toxin blocks these messages.
Botulinum toxin is made by the same bacterium that causes food poisoning. A high dose of botulinum toxin could be fatal, just as food poisoning can be fatal. However, the dose given in injections is so small that you probably won't have any harmful effects from the toxin.
Botulinum toxin has been used safely for a number of years.
Your doctor may be considering botulinum toxin injections to treat certain muscle spasms on your face or eyelids. The injections can also be used for some eye movement disorders, such as a lazy eye (also called strabismus). Botulinum toxin is a standard treatment for spasmodic torticollis, a muscle spasm that causes the head and neck to pull in one direction. Your doctor may use botulinum toxin injections to treat other problems as well.
Botulinum toxin is mixed with saline (salt water) and injected into the muscle with a tiny needle. You may receive 5 to 10 injections.
You might have some soreness at the injection sites. If your injection sites get sore, you can take acetaminophen (one brand name: Tylenol) or ibuprofen (two brand names: Advil, Motrin). You can also put an ice pack on the painful area.
You might also have the following side effects:
Side effects from botulinum toxin injections usually go away quickly.
Written by familydoctor.org editorial staff
Reviewed/Updated: 09/10
Created: 09/00