Acetazolamide and Potassium Flux in Red Blood Cells

Rates of potassium influx in red blood cells of three patients with hyperkalemic periodic paralysis were studied during attack-free states and during induced attacks of weakness. Potassium influx rates were normal when the patients were free of attacks but decreased during attacks. Twenty-four-hour administration of acetazolamide decreased resting potassium influx rates and minimized any further decreases due to the attack-inducing procedures. The data suggest that acetazolamide administration alters potassium exchange rates between intracellular and extracellular compartments in such a way as to protect from sudden upward surges in plasma potassium levels.