Catatonia is a syndrome that has been associated with several mental illness disorders but that has also presented as a result of other medical conditions. Schizophrenia and other psychiatric disorders such as mania and depression are known to be associated with catatonia;
however, several case reports have been published of certain medical conditions inducing catatonia, including hyponatremia, cerebral venous sinus thrombosis, and liver transplantation. Neuroleptic Malignant Syndrome and anti-NMDA receptor encephalitis are also prominent causes of catatonia. Patients taking benzodiazepines or clozapine are also at risk of developing catatonia following the withdrawal of these medications—
it is speculated that the prolonged use of these medications
increases gamma-aminobutyric acid (GABA) activity and
that discontinuation may increase excitatory neurotransmission, leading to catatonia.
Drug-induced catatonia occurs when psychiatric medications, particularly antipsychotics,
disrupt neurotransmitter systems-specifically by blocking dopamine (receptors) or
altering GABA/glutamate balance.
It often acts as a paradoxical reaction, where medication causes the severe motor inhibition and behavioral abnormalities it was intended to treat.
Dopamine Receptor Blockade: High-potency antipsychotics (e.g., risperidone, haloperidol) can severely reduce dopamine activity in the brain, leading to catatonic symptoms, sometimes mimicking or leading to Neuroleptic Malignant Syndrome (NMS).
Withdrawal Mechanisms: Abrupt cessation of substances that increase GABA (like benzodiazepines) or antipsychotics (like clozapine) can trigger a rebound excitation in the central nervous system, resulting in catatonia.
Paradoxical Reaction: Although antipsychotics are used to treat catatonia, they can paradoxically induce it, particularly when initiated or increased rapidly.
Underlying Vulnerability: Patients with underlying mood disorders (e.g., bipolar disorder, depression) or those who have already experienced catatonia are at higher risk.
