Acute dystonia is an extrapyramidal movement disorder which can be caused by the administration of antipsychotics. These drugs will block dopaminergic neurotransmission in the nigrostriatal tract and cause an imbalance in the relative dopaminergic versus cholinergic neurotransmission.
The resulting symptoms can occur suddenly within hours or days of starting the drug or a dose increase. Dystonias are sustained muscle contractions, twisting and repetitive movements or abnormal postures and can include oculogyric crisis, torticollis, opisthotonos, and life-threatening laryngeal dystonias.
Acute dystonias arise from which physiological situation in the nigrostriatal tract?
Extra info: Although the pathophysiology is thought to be due to an imbalance between DA and ACH, the precipitating factor is a drop in DA neurotransmission.
A 20 year old male has his first schizophrenic episode and is treated with haloperidol. On day 2 he is seen with a stiff neck and a protruding tongue. This is a typical presentation of acute dystonia.
Extra info: The only risk factor that this patient is missing is a previous history of dystonia.