Botox is one of the many trade names for the neurotoxic protein called botulinum toxin that is produced by the bacterium Clostridium botulinum. In large doses, the protein causes botulism, a rare paralytic illness often linked to food poisoning.

However, the protein is used in cosmetic medicine to treat moderate to severe brow furrow (glabellar lines), uncontrolled blinking, lazy eye, wrinkles, and facial creases. These procedures use a small amount of diluted botulinum toxin that enables controlled weakening of muscles.

Botulinum toxin is sold commercially under the brand names Botox, BTXA, Dysport, Myobloc, Neurobloc, Xeomin, Botox Cosmetic, and Vistabel.