A large study lasting 17 years and including more than 730,000 people has revealed some surprising results about two common blood pressure medications—chlorthalidone and hydrochlorothiazide.
These medicines are widely used to help lower blood pressure and reduce the risk of heart attacks, strokes, and heart failure.
Researchers from Columbia University led the study, which was recently published in the journal JAMA Internal Medicine. They found that while both drugs work well to control blood pressure, chlorthalidone may come with a much higher risk of side effects than hydrochlorothiazide.
One of the most serious concerns is a condition called hypokalemia, which means low potassium levels in the blood. Potassium is a key mineral that helps the heart and muscles work properly. If potassium levels drop too low, it can lead to serious problems like irregular heartbeats, muscle weakness, confusion, kidney trouble, and even type 2 diabetes.
In the study, about 6.3% of people taking chlorthalidone developed low potassium levels. In comparison, only 1.9% of people taking hydrochlorothiazide had this issue. That means people on chlorthalidone were three times more likely to suffer from low potassium.
The researchers also found that chlorthalidone was linked to more problems with electrolytes and kidney function. These side effects appeared even when people were taking lower doses of the drug.
These findings have raised questions among doctors and experts about whether chlorthalidone should continue to be a first-choice treatment for high blood pressure. Doctors may need to check blood tests more often for patients on chlorthalidone or think about using different medicines.
High blood pressure, also known as hypertension, is a major health problem around the world. If it’s not treated, it can cause serious damage to the heart, brain, kidneys, and other parts of the body. That’s why managing blood pressure is so important.
While medications are important in treating high blood pressure, lifestyle changes also play a big role. Eating healthy foods, exercising regularly, reducing salt and alcohol, quitting smoking, and managing stress can all help keep blood pressure under control. Many doctors also recommend checking your blood pressure at home to stay on track.
The lead researcher, Dr. George Hripcsak, says this study is an important reminder that each patient is different. What works well for one person may not be the best choice for another. That’s why it’s important for doctors and patients to talk about the risks and benefits of each medication and make a treatment plan that fits the patient’s needs.
This study helps healthcare professionals understand which drugs may be safer and more effective for different people. With more research, treatments for high blood pressure can keep improving—helping people live longer, healthier lives.
If you care about blood pressure, please read studies that changing blood pressure readings is a hidden sign of heart disease and switching blood pressure drugs may treat the condition better.
For more information about blood pressure, please read studies about the arm squeeze test: could your blood pressure reading be wrong and bedtime medication more effective for high blood pressure.
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