From the FDA Drug Label
Serum electrolyte levels (particularly potassium) and blood pH levels should be monitored. The FDA drug label does not answer the question.
From the Research
Diamox (acetazolamide) is most likely to cause hypokalemia, not hyperkalemia, due to its mechanism of action as a carbonic anhydrase inhibitor, which promotes potassium excretion in the urine. However, there is a case report that suggests a paradoxical increase in potassium can occur with acetazolamide, as seen in a patient who developed critical hyperkalemia after a single intravenous dose of 1000 mg of acetazolamide 1. The majority of the evidence suggests that acetazolamide leads to hypokalemia, with studies showing a decrease in mean potassium levels during decongestion therapy 2, and a kaliopenic effect in normals and patients with hyperkalemic periodic paralysis 3. Additionally, a study on the effects of acetazolamide as a chloride-regaining diuretic found that the serum potassium concentration constantly decreased throughout the study period 4. It is essential to monitor patients taking acetazolamide for signs of hypokalemia, which may include muscle weakness, fatigue, cardiac arrhythmias, and constipation, and consider potassium supplementation in susceptible individuals. Regular electrolyte monitoring is advisable when starting this medication or adjusting the dosage, especially in patients with pre-existing low potassium levels or conditions like Gitelman syndrome. While the case report of hyperkalemia is notable, the overall evidence supports the notion that hypokalemia is the more common electrolyte disturbance associated with acetazolamide use 2, 3, 4. In clinical practice, it is crucial to be aware of both potential effects, but the primary concern with acetazolamide remains hypokalemia, and patients should be monitored and managed accordingly.