What is botox?

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A neurotoxin produced by bacteria that causes botulism in very high doses and is also used as a therapeutic agent for a variety of conditions.
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Indications and Procedures

Botulinum toxin has found wide applications as an effective treatment for a variety of conditions associated with excessive muscle contractions. A protein produced by the bacterium Clostridium botulinum, botulinum toxin is a potent neurotoxin, causing botulism in very high doses. Botulism is a syndrome of paralysis associated with gastrointestinal symptoms including abdominal cramps and ultimately with respiratory failure from the paralysis of respiratory muscles. As a therapeutic agent, botulinum toxin is injected into muscles and blocks the release of the neurotransmitter acetylcholine from nerve terminals, thus causing paralysis. There are seven different types of botulinum toxin. Two types, botulinum A and B, are available in the United States for clinical use. Botulinum A is also known under the brand name Botox.

Botulinum toxin is available as a purified, vacuum-dried toxin and is reconstituted by the addition of sterile, preservative-free saline. The toxin is then injected into targeted muscles to produce a localized muscle paralysis effect.

Uses and Complications

The utility of botulinum toxin was first demonstrated clinically for the treatment of strabismus, a disorder of abnormal alignment of the eyes. Other disorders treated with botulinum toxin include blepharospasm, a condition of forceful eyelid closure, and focal dystonias, which are syndromes of sustained muscle contractions associated with abnormal postures. Examples of focal dystonias treated with botulinum toxin include cervical torticollis (involuntary neck turning), laryngeal dystonia (abnormal movements of the vocal cords), and oromandibular dystonia (abnormal muscle spasms of the jaw and lower facial muscles). Hemifacial spasm, a disorder of involuntary contractions of the face, also responds well to toxin treatment. Botulinum toxin is also used to treat spasticity, which refers to an excessive increase in muscle tone in the extremities. Hyperhidrosis (excessive sweating) and sialorrhea (hypersalivation) have also been treated with botulinum toxin, with good results reported. Botulinum toxin has achieved much public attention for its cosmetic use as a treatment for facial wrinkles.

The onset of effect of the injection occurs within several days and generally causes weakness and muscle atrophy for approximately several months, with the effect wearing off gradually. Side effects of botulinum toxin treatment are generally transient and may be the result of a local effect of injection, such as bruising, or related to diffusion of the toxin to nearby muscles. The potential side effect encountered depends on the location of injection. For example, injection into neck muscles has the potential side effects of excessive weakness or dysphagia (difficulty swallowing). Over time, some patients may develop resistance to the effects of the medication, which may be associated with the development of neutralizing antibodies.


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