Background: hyperkalaemic paralysis is a rare, treatable, and potentially fatal entity presenting with flaccid motor weakness.
Case report: a patient with acute hyperkalaemic paralysis caused by erroneous oral potassium supplementation in the context of chronic renal failure. The clinical picture of quadriplegia was initially interpreted as spinal cord injury due to a pathological cervical fracture.
Discussion: the diagnosis of hyperkalaemic paralysis requires a high index of suspicion. Instructions for over-the-counter supplements must be clear and concise to prevent life-threatening medication errors.