A client has been receiving chlorpromazine (Thorazine), an antipsychotic, to treat his psychosis. Which findings should alert the nurse that the client is experiencing pseudoparkinsonism?
A. Restlessness, difficulty sitting still, and pacing
B. Involuntary rolling of the eyes
C. Tremors, shuffling gait, and masklike face
D. Extremity and neck spasms, facial grimacing, and jerky movements
Correct Answer: C. Tremors, shuffling gait, and mask-like face
Pseudoparkinsonism may appear 1 to 5 days after starting an antipsychotic and may also include drooling, rigidity, and “pill-rolling.” Despite being a low-potency drug, chlorpromazine can still cause extrapyramidal side effects (EPS) such as acute dystonia, akathisia, parkinsonism, and tardive dyskinesia (TD). The evolution of EPS side effects can occur through hours to days. Acute dystonia refers to muscle stiffness or spasm of the head, neck, and eye muscles that can start hours after starting the medication. Akathisia includes restlessness and fast pacing. Parkinsonism includes bradykinesia, “cogwheel” rigidity, and shuffling gait.
Option A: Akathisia may occur several weeks after starting antipsychotic therapy and consists of restlessness, difficulty sitting still, and fidgeting. Patients are at risk of developing neuroleptic malignant syndrome (NMS), which is a life-threatening manifestation, where the patient presents with “lead-pipe” muscle rigidity, autonomous instability, hyperpyrexia more than 40 degrees Celsius, altered mental status, leukocytosis, and elevated serum creatinine kinase.
Option B: An oculogyric crisis is recognized by uncontrollable rolling back of the eyes and, along with dystonia, should be considered an emergency. Chlorpromazine use also requires caution in patients with cerebrovascular and cardiovascular diseases. Patients should start on a low dose of chlorpromazine as an initial dosage, and the increase in subsequent dosing should be gradual. However, treatment should be discontinued if the patient develops agranulocytosis.
Option D: Dystonia may occur minutes to hours after receiving an antipsychotic and may include extremity and neck spasms, jerky muscle movements, and facial grimacing. Chlorpromazine belongs to the category of typical antipsychotics or neuroleptics, also known as first-generation antipsychotics (FGAs). It produces its antipsychotic effect by the post-synaptic blockade at the D2 receptors in the mesolimbic pathway. However, the blockade of D2 receptors in the nigrostriatal pathway is responsible for its extrapyramidal side effects.