Botulinum toxin A is successfully used to treat blepharospasm and strabismus, and botulinum toxin B has proven useful in treating cervical dystonia -- these are all conditions that in some way involve spasms, involuntary muscle contractions. Within a few hours to a couple of days after the botulinum toxin is injected into the affected muscle(s), the spasms or contractions are reduced or eliminated altogether. The effects of the treatment are not permanent, reportedly lasting anywhere from three to eight months. By injecting the toxin directly into a certain muscle or muscle group, the risk of it spreading to other areas of the body is greatly diminished.
When Botox -- botulinum toxin A -- is injected into the muscles surrounding the eyes, for instance, those muscles can not "scrunch up" for a period of time. They are paralyzed. So the wrinkles in that area, often referred to as "crow's-feet," temporarily go away. Side effects may include dysphasia, upper respiratory-tract infection, headache, neck pain, ptosis, bruising/soreness and nausea.
Other applications for Botox are currently under investigation. It has been reported that spasmodic dysphonia, a neurological disorder that affects the muscles of the larynx, responds well to Botox treatment. It has also been used to treat other dystonias, such as writer's cramp, as well as facial spasms, head and neck tremors and hyperhidrosis (excessive sweating.)
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