Medication Summary
The goals of pharmacotherapy are to reduce morbidity and prevent complications. Anticholinergic agents and benzodiazepines are most often used.
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 treatments, and data do not support one over the other.
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, benztropine may help in balancing cholinergic and dopaminergic activity.
Diphenhydramine (Benadryl)
Although an antihistamine, diphenhydramine also possesses significant anticholinergic properties. The 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 when anti-muscarinic agents are not approporiate.
Diazepam (Valium)
Some recommend using diazepam for patients with dystonic reactions refractory to anticholinergic therapy or when such therapy is contraindicated.
