Multiple Sclerosis (MS) is a condition that damages the nerves, disrupting and throwing out of sync the signals that they send to the body's muscles. That causes the muscles to tense up and move in ways that they don't want to, a condition called spasticity.
Botox, fortunately, offers MS patients some relief from that condition. The toxin blocks acetylcholine, the chemical that transmits those garbled nerve signals, and that allows muscular relaxation [source: WebMD].
For Botox treatments to work effectively, a doctor may need to record electrical signals from the patient's body in order to determine which muscles are getting mixed-up signals. That way, the drug can be injected in the places where it will help. Usually, the treatment starts to work after a week or two, and the effect lasts for two to six months [source: WebMD].
A 2012 study also found that botulinum toxin may help prevent shaking and tremors in the arms and hands of MS patients, another persistent problem that they face. The researchers reported that patients' tremor severity improved by an average of two points on a 10-point scale (which indicated moderate symptoms being reclassified as mild), and that they showed improvement in their ability to write and draw [source: ScienceDaily].