Life‐Threatening Bradycardia due to Clonidine and Lacosamide Interaction in a Hemodialysis Patient: A Case Report

A 66‐year‐old male with end‐stage renal disease (ESRD) on maintenance hemodialysis presented to the emergency department (ED) with life‐threatening bradycardia and hypotension, potentially due to a drug–drug interaction (DDI) with his current medications (lacosamide and clonidine). His medical history included seizure disorders, hypertension, and ischemic stroke. Initial management included intravenous atropine, calcium gluconate, and sodium bicarbonate. Both medications were discontinued, and the patient underwent hemodialysis with monitoring in the intensive care unit. Diagnostic evaluations such as electrocardiograms (ECG) and Holter monitoring showed a normal sinus rhythm with occasional isolated supraventricular ectopics. By Day 3, the patient′s heart rate normalized (76–81 beats/min) and hypotension resolved. He was discharged on hospital Day 4 with cardiology and nephrology follow‐up and instructions on avoiding the use of clonidine and lacosamide. To our knowledge, this is the first reported case of clonidine‐lacosamide interaction in patients with renal impairment. It underscores the risk of exacerbated bradycardia due to reduced drug clearance in ESRD. Clinicians should exercise caution when prescribing these medications, consider alternative treatments, implement dose adjustments, and maintain heightened vigilance to mitigate risks. Multidisciplinary care involving nephrologists, cardiologists, and clinical pharmacists is required to ensure patient safety in this vulnerable population.