A new study from Columbia University suggests that chlorthalidone, a commonly prescribed diuretic for lowering blood pressure, may cause more serious side effects than hydrochlorothiazide, another diuretic with similar effectiveness. These findings challenge current medical guidelines, which recommend chlorthalidone as the preferred option.
Researchers analyzed 17 years of data from more than 730,000 people who were treated for high blood pressure. They found that both chlorthalidone and hydrochlorothiazide were equally effective in reducing the risk of heart attacks, hospitalizations for heart failure, and strokes.
However, patients taking chlorthalidone had a significantly higher risk of severe side effects, including dangerously low potassium levels, electrolyte imbalances, and kidney problems.
One of the most concerning side effects was hypokalemia (low potassium), which can lead to abnormal heart rhythms. The study found that 6.3% of patients taking chlorthalidone developed hypokalemia, compared to only 1.9% of those on hydrochlorothiazide. Even when prescribed at lower doses, chlorthalidone still had higher rates of this condition.
Other side effects linked to chlorthalidone included hyponatremia (low sodium), which can cause confusion, kidney failure, and an increased risk of developing type 2 diabetes.
The researchers recommend that doctors carefully monitor patients who are prescribed chlorthalidone for potential side effects. This study is not the first to raise concerns about the drug. Previous research also linked it to more electrolyte imbalances than hydrochlorothiazide.
Given these findings, the study suggests that medical guidelines may need to be reevaluated to ensure that patients receive the safest treatment options.
The study, led by George Hripcsak, was published in JAMA Internal Medicine.
If you care about high blood pressure, please read studies that early time-restricted eating could help improve blood pressure, and natural coconut sugar could help reduce blood pressure and artery stiffness.
For more information about blood pressure, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
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