Clozapine-induced Tardive Dyskinesia in Middle-aged Patient of Schizophrenia which Responded to Zolpidem

Clozapine is an atypical antipsychotic used in the treatment of refractory schizophrenia. It has a well-known side effect profile, including agranulocytosis, hypersalivation, constipation, decreased seizure threshold, postural hypotension, and myocarditis. Clozapine is generally not associated with tardive dyskinesia (TD). TD is an agonizing side effect of long-term use of antipsychotics, mainly first-generation or typical antipsychotics, but though uncommon, it can also occur with prolonged use of second-generation or atypical antipsychotics. TD, if not identified early in its course of development, can become irreversible. Clozapine, due to its unique low affinity for striatal D2 receptors, is relatively free from TD, and due to its antiserotonergic (5HT2, 5HT1C) and anticholinergic properties, it is often found to be therapeutic in drug induced, even drug-naïve patients with TD. However, it is also found to be associated with the development of TD in patients with different psychiatric disorders. Here, we present a case of clozapine-induced TD following the long use of clozapine monotherapy, where symptoms of TD improved with the addition of zolpidem in the treatment regimen.