Involuntary contraction sustained in one or several muscles due to medication.
It is usually due to newly developed drugs, although it can occur with long-standing treatment. The most frequently involved are: dopaminergic blockers (including neuroleptics), antiemetics (metroclopramide), antivertiginants (thiethylpiperazine), antiepileptics (carbamazepine, gabapentin) and antidepressants (fluoxetine, paroxetine and amitriptyline).
The most frequently affected muscles are those of the neck, arms and legs. They manifest with muscle stiffness and pain, repetitive movements and tremors.
Diagnosis is clinical, through questioning of substance use.
Treatment is aimed at reducing muscle contractions and pain, which lead to a limitation of activities of daily living. It can be achieved with medication, botox injections, surgery, physical therapy or a combination of those.
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- Cynthia Comella, MD. Treatment of dystonia. UpToDate. Oct 07, 2016.
- Albanese A, Asmus F, Bhatia KP, et al. EFNS guidelines on diagnosis and treatment of primary dystonias. Eur J Neurol 2011; 18:5.
