Botulinum Toxin Injection

Botulinum toxin is a complex mixture of proteins that include a botulinum neurotoxin and several nontoxic proteins, produced by Clostridium botulinum. The effect of botulnum toxin is to paralyze muscles. It was first purified in 1945, but its therapeutic use was only initiated in the 1980s by Alan B Scott in patients with crossed eyes (strabismus).

Indications for botulinum toxin include involuntary muscle contractions (dystonia), excessive eye blinking (blepharospasm), some forms of speech or swallowing dysfuncitons, facial twitching (hemifacial spasm) ,  and tics

The improvement of the symptoms, after the injection of the botulinum toxin in the muscles, usually occurs in 1 to 14 days. The peak effect is expected for 2–6 weeks, and loss of effect starts within 10–12 weeks. Some degree of muscular shrinkage or atrophy is observed after 1–2 weeks of treatment and a return to about 70–80% of muscle mass is noted after 3 months.