Symptoms
Clinical signs and symptoms of potassium overdosage include:
Paraesthesia of the extremities, listlessness, mental confusion, weakness or heaviness of the legs, flaccid paralysis, cold skin, grey pallor, peripheral vascular collapse, fall in blood pressure, cardiac arrhythmias and heart block.
Extremely high plasma potassium concentrations (8-11 MMOL/litre) may cause death from cardiac depression, arrhythmias or arrest.
Treatment
Cardiac arrhythmias or a serum concentration above 6.5 MMOL/litre, require immediate attention and may be treated by intravenous injection over 1-5 minutes of 10 – 20 ml of 10% Calcium Gluconate Injection with ECG monitoring.
Serum concentrations of potassium may be reduced by infusion of 300 – 500 mls per hour of 10%-25% glucose solutions containing up to 10 units of insulin for each 20 g of glucose, or by the infusion of sodium bicarbonate solution.