Life-threatening hyperkalaemia developing following excessive ingestion of orange juice in a patient with baseline normal renal function.

Hyperkalaemia is a less-recognised life-threatening cause of paralysis. We describe a 51-year-old African-American man, who suffered from muscle weakness progressing to ascending symmetric paralysis, and inability to masticate. Physical examination revealed flaccid paralysis with areflexia of the four limbs. Computed tomography of the brain and cervical spine did not demonstrate any organic lesions. Laboratory investigations revealed serum potassium 9.0 mEq/L (not haemolysed), blood urea nitrogen 34 mg/dL, and serum creatinine 2.0 mg/dL. Electrocardiography showed typical features of hyperkalaemia. After emergent treatment for hyperkalaemia was initiated, serum potassium was rapidly-normalised to 5 mEq/L and all neuromuscular symptoms reversed within one hour. Upon reviewing his food and medication history, he admitted drinking 2.5 litres of orange juice (which contains about 450 mg of potassium in 1,000 ml) per day for the past three weeks to quench his thirst. Hyperkalaemia should be borne in mind in the differential diagnosis of acute paralysis. Hidden sources of potassium intake, such as orange juice, should not be overlooked, even in patients with baseline normal renal function.