onabotulinumtoxinA, Botox, Botox Cosmetic

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GENERIC NAME: onabotulinumtoxinA

BRAND NAME: Botox, Botox Cosmetic

DRUG CLASS AND MECHANISM: OnabotulinumtoxinA is an injectable neuro-toxin, that is, a toxic chemical that blocks the ability of nerves to make muscles contract. In other words, it paralyzes muscles.

To cause muscles to contract, nerves release a chemical, acetylcholine, where they meet muscle cells. The acetylcholine attaches to receptors on the muscle cells and causes the muscle cells to contract or shorten. OnabotulinumtoxinA prevents the release of acetylcholine and thereby prevents contraction of the muscle cells. In order to affect the release of acetylcholine, onabotulinumtoxinA must be injected into the muscle. OnabotulinumtoxinA was approved by the FDA in December 1991.

PRESCRIBED FOR: OnabotulinumtoxinA is used for the treatment of chronic migraine, axillary hyperhidrosis (excessive sweating in the armpits), and spasticity of the upper arms.

It also is used for cervical dystonia (spasm of the muscles of the neck) to reduce the abnormal head position and neck pain caused by the muscular spasm.

Medically Reviewed by a Doctor on 7/23/2015

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