Dystonia is an involuntary movement characterized by abnormal muscle contractions that cause repetitive postures and twisting movements.
Botulinum toxin injections are highly effective in controlling symptoms of dystonia that are localized. As injections only target muscles involved in the abnormal movements, there are no adverse side effects on the brain. Botulinum toxin injections are given every 3-4 months on average for dystonia due to the return of symptoms. The side effects of therapy can include weakness of the injected muscle or temporary difficulty with swallowing if muscles are injected in the neck. An ultrasound machine or an electromyogram machine may be used to help locate muscles for precise injections.