Scientists from Columbia University have discovered that a widely recommended blood pressure drug, chlorthalidone, may cause more serious side effects than another commonly used medication, hydrochlorothiazide.
Despite both drugs being equally effective in lowering blood pressure and preventing heart-related issues, the findings challenge current treatment guidelines.
The study analyzed 17 years of data from more than 730,000 patients receiving treatment for high blood pressure. Researchers found that both chlorthalidone and hydrochlorothiazide were similarly effective at preventing heart attacks, strokes, and hospitalizations for heart failure.
However, patients taking chlorthalidone were nearly three times more likely to develop dangerously low potassium levels (hypokalemia) compared to those taking hydrochlorothiazide.
Hypokalemia can lead to serious complications, including abnormal heart rhythms, muscle weakness, and fatigue. In the study, 6.3% of patients taking chlorthalidone developed this condition, compared to only 1.9% of those on hydrochlorothiazide. Even at lower doses, chlorthalidone still caused more cases of low potassium than hydrochlorothiazide.
Beyond potassium imbalances, researchers also found that chlorthalidone was linked to a higher risk of other electrolyte disturbances, low sodium levels (hyponatremia), kidney problems, and even an increased risk of type 2 diabetes. These imbalances can cause confusion, weakness, kidney failure, and other serious health problems.
Doctors have long favored chlorthalidone over hydrochlorothiazide based on guidelines that suggest it provides longer-lasting effects. However, this study raises concerns about its safety and suggests that doctors should carefully monitor patients taking chlorthalidone for potential side effects.
This is not the first study to highlight concerns about chlorthalidone. Earlier research also linked it to more electrolyte imbalances compared to hydrochlorothiazide. The new findings add to growing evidence that treatment recommendations may need to be reconsidered.
The study, led by George Hripcsak, was published in JAMA Internal Medicine. It underscores the importance of balancing effectiveness with safety when choosing medications for high blood pressure.
If you’re interested in learning more about blood pressure management, recent studies have explored how cannabis may help reduce blood pressure in older adults and how certain plant nutrients might lower hypertension.
Other research has looked at strategies for living with high blood pressure and even unexpected links between common toothpaste ingredients and inflammation in the gut.
As always, it’s essential for patients to discuss medication options with their doctors to find the safest and most effective treatment for their individual needs.
If you care about high blood pressure, please read studies about unhealthy habits that may increase high blood pressure risk, and drinking green tea could help lower blood pressure.
For more information about high blood pressure, please see recent studies about what to eat or to avoid for high blood pressure, and 12 foods that lower blood pressure.
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