Toxicity, Medication-Induced Dystonic Reactions Medication
- Author: Geofrey Nochimson, MD; Chief Editor: Asim Tarabar, MD more...
Medication Summary
The goals of pharmacotherapy are to reduce morbidity and prevent complications.
Anticholinergic agents
Class Summary
The goals of pharmacotherapy are to reduce morbidity and prevent complications. The most commonly used agents are benztropine and diphenhydramine. Both are effective, and limited data supports one more than the other as the treatment of choice.
IV is the route of choice, with signs and symptoms often resolving within 10 minutes. The medication can be delivered IM if an IV line cannot be established, but medications will take 30 min to be absorbed. More than 1 dose may be necessary for complete resolution of dystonia.
Benztropine (Cogentin)
By blocking striatal cholinergic receptors, may help in balancing cholinergic and dopaminergic activity.
Diphenhydramine (Benadryl)
Although an antihistamine, also possesses significant anticholinergic properties. Mechanism of action is identical to that of benztropine.
Benzodiazepines
Class Summary
Normal balance between dopamine and acetylcholine in the basal ganglia involves modulation from GABA-containing striatonigral neurons. GABA-ergic neurons are inhibitory and antagonize excitatory dopaminergic neurons. GABA agonists (eg, benzodiazepines) may be helpful for acute dystonic reactions.
Diazepam (Valium)
Some recommend using for patients with dystonic reactions refractory to anticholinergic therapy or when such therapy is contraindicated.
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