Abstract
Gastrointestinal hypomotility (GIH) represents a significant yet underrecognized adverse effect of antipsychotic medications that can lead to severe complications. We present the case of a 37-year-old male with schizophrenia on first- and second-generation antipsychotics who presented to the emergency department with acute diffuse abdominal pain. Physical examination revealed a distended, silent, and diffusely tender abdomen along with compromised ventilatory mechanics and signs of peripheral hypoperfusion. Laboratory evaluation demonstrated elevated inflammatory markers, acute kidney injury, and hyperlactatemia. Abdominal computed tomography revealed significant small and large bowel distention without mechanical obstruction and a collapsed inferior vena cava. Despite initial treatment with laxatives, the patient's clinical condition rapidly deteriorated into a peri-arrest state requiring emergency department admission. Under the working diagnosis of obstructive shock secondary to abdominal compartment syndrome, the patient underwent emergent decompressive laparotomy with immediate hemodynamic and respiratory improvement. Intraoperative findings revealed markedly distended small and large bowels with evidence of colonic unviability, necessitating total colectomy. Following a comprehensive evaluation, antipsychotic-induced GIH was determined to be the most probable underlying pathophysiological mechanism. This case illustrates a severe manifestation of antipsychotic-induced GIH and emphasizes the critical importance of prevention strategies and early recognition of this potentially life-threatening condition.