Botox injections are noted primarily for the ability to reduce the appearance of facial wrinkles. They're also used to treat conditions such as neck spasms (cervical dystonia), excessive sweating (hyperhidrosis), an overactive bladder and lazy eye. Botox injections may also help prevent chronic migraines.
Botox injections use a toxin called onobotulinumtoxinA to temporarily prevent a muscle from moving. This toxin is produced by the microbe that causes botulism, a type of food poisoning.
Botox was the first drug to use botulinum toxin. Other products now include abobotulinumtoxinA (Dysport), rimabotulinumtoxinB (Myobloc) and incobotulinumtoxinA (Xeomin). Each is a little different, particularly when it comes to dosage units, so they aren't interchangeable.