Amitriptyline overdose—an uncommon cause of acute transient exotropia presenting to the emergency setting: a case report

BACKGROUND: Acute presentations of acquired exotropia or divergent alignment of either or both eyes are commonly observed following intracranial vascular events, trauma, orbital, and endoscopic sinus surgeries. CASE PRESENTATION: The reported case is about a 16-year-old previously healthy Tamil female who presented to the emergency department with a few hours of reduced responsiveness. With the only clue in the history being about a family conflict the previous day, the examination revealed a noticeable exotropia along with a constellation of anticholinergic findings: a low Glasgow Coma Score, mydriasis, tachycardia, floppy limbs, exaggerated reflexes, and a palpable urinary bladder. Amitriptyline overdose leading to significant neurological involvement was suspected, and she was immediately offered urine alkalinization. Resources for urine and blood toxicological studies were not available. The patient gained consciousness 24 hours later and confirmed an overdose of ten amitriptyline tablets. Exotropia, a unique manifestation of this patient’s neurotoxicity, spontaneously resolved in 36 hours. DISCUSSION AND CONCLUSIONS: The reported case is about an uncommon clinical finding of exotropia seen in a common toxicological emergency: acute amitriptyline overdose. The importance of having a wide knowledge of various clinical presentations of drug toxicities is highlighted here, as any delay in diagnosis or initiation of life-saving measures could have resulted in fatal consequences.