Case ReportGlucagon-induced hypertensive emergency: a case report

•Glucagon is a sphincter of Oddi relaxant and also an empiric treatment for β-blocker overdose.•Our patient experienced a hypertensive emergency due to acute β-blockade reversal.•Glucagon-induced crises have been observed in patients with asymptomatic pheochromocytoma.•Glucagon has potentially severe hemodynamic effects even in healthy populations.

Glucagon is well acknowledged as a sphincter of Oddi relaxant for both diagnostic and therapeutic uses in choledocholithiasis, and an empiric treatment for β-blocker overdose. Although it has been implicated in inducing cardiovascular crises in patients with asymptomatic pheochromocytoma, adverse effects in other patient populations have not been characterized. This case report describes a patient with hypertension controlled on β blockers who, after glucagon administration during an intraoperative cholangiography, experienced hypertensive emergency despite adequate pain control. Nitroglycerin acted as a key agent to decrease the patient's blood pressure as well as a secondary relaxant of the sphincter of Oddi. The patient had no radiographic evidence of pheochromocytoma. As out-of-operating room and intraoperative uses of glucagon continue to increase, perioperative physicians should be aware of its potential hemodynamic effects even in healthy populations.