Potassium chloride poisoning can occur with significant overdoses of oral or intravenous (IV) potassium supplementation, leading to hyperkalemia. Hyperkalemia is defined as serum potassium greater than 5-5.5 mEq/L. When serum potassium reaches 7 mEq/L or higher, there is significant risk for acute life-threatening complications. Symptoms include paralysis or muscle weakness, chest palpitations, arrhythmias, and gastrointestinal distress.

Excess potassium is physiologically excreted by the kidneys. Therefore, serum potassium is much more likely to reach toxic levels in patients with significant renal disease. Due to gastrointestinal regulatory mechanisms, poisoning is more likely to occur with IV potassium administration.

Emergent treatment includes IV calcium, insulin, and bicarbonate. Albuterol, potassium-binding agents, and hemodialysis are sometimes used.