Systemic Epinephrine Toxicity Following Topical Anesthetic Gel on Mucosal Surfaces: A Case Report and Literature Review.

Introduction: Systemic toxicity from topical epinephrine is rare because dermal and mucosal absorption is typically limited. However, application to highly vascular mucosa, particularly under occlusion, may result in clinically significant systemic absorption. Case presentation: A 42-year-old woman developed severe headache, palpitations, tremor, and marked hypertension shortly after a compounded 2.5% lidocaine with epinephrine (1:2000; 0.5 mg/mL) gel was applied to the labial mucosa under occlusion during a cosmetic procedure. An estimated 0.5 to 1.5 mg of epinephrine was applied. Symptoms began within 10 minutes and persisted until gel removal approximately 25 minutes later. On EMS arrival, heart rate was 145 bpm and blood pressure 210/110 mmHg. In the emergency department, ECG showed sinus tachycardia without ischemic changes; laboratory studies were unremarkable except for mild respiratory alkalosis, and serial high-sensitivity troponin I was negative. Management included prompt removal of the topical agent, supportive care, and cardiac monitoring. Symptoms resolved spontaneously without pharmacologic intervention, and the patient was discharged after 4 hours of observation. Conclusion: Topical epinephrine applied to highly vascular mucosal surfaces-especially under occlusion-can rarely cause systemic sympathomimetic toxicity characterized by hypertension, tachycardia, tremor, and anxiety. Although it may resemble local anesthetic systemic toxicity, it is clinically distinct. Careful dosing, avoidance of occlusive dressings, close monitoring, and immediate removal of the agent at the first sign of systemic effects are essential to prevent complications.