C53-52 Coconut Water-induced Hyperkalemia- Unmasking a Natural Cause of Bradyarrhythmia

Introduction Over the past couple of years, an increasing number of people have turned to consuming coconut water for its purported health benefits. Although generally safe in moderation, excessive intake of coconut water has been associated with rare but clinically significant electrolyte disturbances, leading to cardiac arrhythmias. Recognition of this potential risk is essential, particularly in patients with renal dysfunction, those on potassium-sparing medications, or individuals consuming large quantities of coconut water over a short period. Case Presentation A 54-year-old male with a past medical history of chronic systolic heart failure and chronic kidney disease stage IIIb presented to the hospital with chest discomfort for one day. He was evaluated by a cardiologist two weeks before, for postural hypotension, and was instructed to increase fluid intake to a total of two liters/day. He then started consuming 3-4 liters of coconut water daily. His pertinent home medications were sacubitril-valsartan and spironolactone. Three months earlier, his potassium was 4.1, and he had been on the above medications for the last eight months. The only acute change was the excessive intake of coconut water. On presentation, he was diaphoretic with a heart rate in the 30s, for which he was transcutaneously paced. The patient’s potassium was 8.1, and his EKG showed a peaked T wave and PR interval prolongation. The patient was treated with 1g of calcium gluconate, 10 U of insulin with 50 cc of dextrose, and sodium zirconium cyclosilicate 10g. He was admitted to the intensive care unit, where he received additional potassium shifting therapy. The repeat electrocardiogram showed a sinus rhythm after potassium shifting, and the repeat potassium level downtrended to 4.7. Discussion Coconut water is recognized as a rich source of potassium and has been extensively promoted in the last two decades for its practical use as an electrolyte replacement. However, different brands have varying amounts of potassium. For example, in the above case, more than 500 mg of potassium was present in eight fluid ounces, whereas the daily potassium requirement, according to many guidelines, is 3400 mg/day. As a result, the patient presented to the ED with hyperkalemia, symptomatic bradycardia, and had to be paced, as he received potassium shifting therapy. Coconut water, though beneficial, can raise potassium levels and cause hyperkalemia. This risk should not be disregarded, especially in patients with heart failure or those taking potassium-sparing diuretics due to potential cardiac complications.