Botox is an injectable medication used to treat a variety of conditions including headaches, overactive bladder, upper limb spasticity (increased muscle stiffness in the elbow, wrist, and fingers), and severe underarm sweating. Botox Cosmetic is used to lessen the appearance of wrinkles between the eyebrows.

Botox is made from a toxin produced by Clostridium botulinum bacteria; the same toxin that causes botulism.

In small doses, the toxin blocks nerve signals to certain muscles, alleviating muscle spasm, and other symptoms. When injected into a sweat gland, Botox decreases the activity of the gland to reduce sweating.

Side effects can include pain at the injection site, flu-like symptoms, headache, droopy eyelids, and upset stomach.