Chlorthalidone is associated with a higher risk of hypokalemia compared to hydrochlorothiazide
Chlorthalidone and hypokalemia
- Pharmacological profile: Chlorthalidone is an oral diuretic with a prolonged action of 48–72 hours. It is primarily excreted unchanged by the kidneys and produces a copious diuresis with greatly increased excretion of sodium and chloride
- Clinical studies: In a cohort study, chlorthalidone use was associated with a higher risk of hypokalemia compared to hydrochlorothiazide use . This finding was also supported by a large-scale observational comparative cohort study, which found that chlorthalidone was associated with a significantly higher risk of hypokalemia compared to hydrochlorothiazide
Hydrochlorothiazide and hypokalemia
- Pharmacological profile: Hydrochlorothiazide is another commonly used diuretic in the management of hypertension
- Clinical studies: In the same studies mentioned above, hydrochlorothiazide was associated with a lower risk of hypokalemia compared to chlorthalidone
In conclusion, while both chlorthalidone and hydrochlorothiazide can cause hypokalemia, chlorthalidone is associated with a higher risk. Therefore, careful monitoring of serum potassium levels is essential when initiating or adjusting doses of these medications, especially chlorthalidone. Potassium supplementation may be necessary in some cases to maintain serum potassium levels ≥ 4.0 mmol/L, particularly in patients with hypertension