Acute catatonia and psychosis in the context of seizure exacerbation in epilepsy: a case report.

Background: The co-occurrence of seizure-associated psychosis and catatonia in epilepsy is diagnostically challenging, particularly when complex pre-existing psychiatric comorbidities complicate attribution. Few reports describe this triad in the context of an antidepressant switch. Case presentation: We report a 44-year-old woman with a 27-year history of epilepsy, maintained on carbamazepine and topiramate, and a longstanding psychiatric history of major depressive disorder, obsessive-compulsive symptoms, and chronic nihilistic delusions and intermittent hallucinations documented at baseline. One week before admission, her antidepressant was switched from clomipramine to venlafaxine 150 mg/day. Her caregiver reported increased seizure frequency, culminating in a breakthrough seizure 48 hours before presentation. She then developed acute mutism, food refusal, and unresponsiveness. On admission she met DSM-5-TR criteria for catatonia (mutism, stupor, posturing, waxy flexibility), which gradually resolved over the admission. Electroencephalography under sedation following benzodiazepine administration showed no epileptiform activity, though sensitivity for non-convulsive status epilepticus was limited. Electrocardiography demonstrated QTc prolongation (497 ms). Once verbal, the patient reported persecutory and nihilistic delusions, derealization, and auditory hallucinations. Management with escalating benzodiazepines and cautious antipsychotic uptitration (quetiapine XR, cariprazine) was associated with complete catatonic remission and psychotic symptom resolution over 29 days. Discussion: This case illustrates the diagnostic uncertainty inherent in attributing acute psychiatric features to seizure activity when complex pre-existing psychiatric histories exist. The absence of a documented lucid interval and the presence of chronic baseline psychotic symptoms preclude a confident diagnosis of postictal psychosis; interictal psychosis or primary psychiatric disorder cannot be excluded. The case highlights underrecognized pharmacokinetic interactions between carbamazepine (a potent CYP3A4 inducer) and second-generation antipsychotics, and cardiac safety considerations during antipsychotic uptitration with QTc prolongation. Conclusion: The working discharge diagnosis was catatonic disorder due to another medical condition (epilepsy), with psychotic features of indeterminate classification. Clinicians should resist anchoring on temporal associations between seizure activity and psychiatric symptoms. EEG findings must be interpreted in their pharmacological context; pharmacokinetic interactions should inform antipsychotic dose selection; and QTc prolongation warrants structured cardiac monitoring.