Review Question - QID 220745

This patient with involuntary movements in the setting of antipsychotic use most likely has tardive dyskinesia. Given that he has been refractory to multiple previous medications, his medication should be switched to clozapine.

Antipsychotic medications can be used as antidepressants, antipsychotics, mood stabilizers, and anxiolytics. They are divided into typical and atypical agents that function through different mechanisms. Typical antipsychotics include haloperidol, trifluoperazine, fluphenazine, thioridazine, and chlorpromazine. They are associated with extrapyramidal side effects including dystonia, akathisia, tardive dyskinesia, and muscarinic side effects. Atypical antipsychotics include olanzapine, clozapine, quetiapine, aripiprazole, risperidone, and ziprasidone. Patients who are resistant to multiple lines of therapy should be started on clozapine. Clozapine is the most effective medication, but also has the rare but serious side effect of agranulocytosis, so patients should be monitored with intermittent complete blood counts.

De la Chappelle et al. studied the side effects of clozapine. They found an incidence of agranulocytosis in 2.1 per every 1000 patient-months of treatment with clozapine. They recommended being aware of this side effect, which is now the foundation for the black box warning that clozapine currently holds.

Figure/Illustration A is a clinical photograph demonstrating tongue fasciculations (red circle). This finding is consistent with a diagnosis of tardive dyskinesia.

Incorrect Answers:
Answer 1: Add diphenhydramine would be appropriate in the treatment of acute dystonia. This extrapyramidal side effect presents hours to days after the start of a new antipsychotic medication. It presents with muscle spasms and trouble swallowing.

Answer 2: Add propranolol would be appropriate in the treatment of akathisia. This extrapyramidal side effect usually presents months after the start of a new antipsychotic medication. It presents with a sustained feeling of motion/restlessness.

Answer 3: Discontinue antipsychotics completely would not be appropriate in this patient who had multiple psychotic episodes requiring hospitalization while not on medication. Switching to clozapine is the most appropriate step as this is a final tier medication for refractory patients.

Answer 5: Switch to olanzapine would not be appropriate in this patient who has already failed multiple other courses of therapy. Another atypical antidepressant is unlikely to work. Clozapine is the most appropriate choice for refractory patients.

Bullet Summary:
Patients with schizophrenia who have been refractory to multiple courses of medications should be started on clozapine.