Guanfacine poisoning resulting in transient ST-segment elevation: a case report.

ABSTRACT

BACKGROUND: Guanfacine is an alpha-2 adrenergic agonist that decreases norepinephrine release and sympathetic outflow. With the increased use of guanfacine for attention-deficit hyperactivity disorder (ADHD), reports of guanfacine poisoning have also risen. CASE PRESENTATION A 15-year-old male (height 170 cm, weight 48 kg), who was taking 2 mg/day of guanfacine for ADHD, was brought to our emergency department after ingesting 40 tablets of guanfacine due to poor exam results. He presented with impaired consciousness and sinus bradycardia on an electrocardiogram (ECG), leading to diagnosis of guanfacine poisoning. Gastric lavage (5 L) was performed, and activated charcoal was administered. Although his consciousness gradually recovered, he developed ST-segment elevation on the ECG. Despite the absence of chest pain and elevated myocardial enzymes, coronary artery stenosis was not observed on coronary artery computed tomography. As his blood guanfacine level decreased, his ECG returned to normal. CONCLUSIONS: This case highlights the need for careful monitoring of guanfacine poisoning patients due to the potential for various cardiovascular events.