A new study from Columbia University has raised important questions about one of the most common medications used to treat high blood pressure. The study looked at two drugs: chlorthalidone and hydrochlorothiazide.
These medications are known as diuretics, or “water pills.” They help the body get rid of extra salt and water through urine, which helps lower blood pressure.
Doctors have often chosen chlorthalidone over hydrochlorothiazide because it stays in the body longer and was thought to have stronger effects. Medical guidelines have even recommended chlorthalidone as the better option. But this new study shows that idea might need to change.
Researchers reviewed 17 years of medical records from over 730,000 patients who were being treated for high blood pressure. They found that both drugs worked equally well to lower the risk of major heart problems. This includes heart attacks, strokes, and heart failure. So when it comes to protecting the heart, neither drug was better than the other.
However, there was a big difference in side effects. People taking chlorthalidone were more likely to have low potassium levels. This condition is called hypokalemia. Potassium is a mineral that helps keep your heartbeat steady.
If potassium levels drop too low, it can lead to dangerous heart rhythms and other serious health issues. In the study, 6.3% of patients taking chlorthalidone developed low potassium, compared to only 1.9% of those on hydrochlorothiazide.
Chlorthalidone also seemed to raise the risk of other problems. These include low sodium levels, which can lead to confusion and kidney problems, and a higher risk of developing type 2 diabetes. Even at lower doses, people taking chlorthalidone still had more side effects than those taking hydrochlorothiazide.
Because of this, doctors may need to be more careful when prescribing chlorthalidone. People who use this drug might need regular blood tests to check their potassium and sodium levels and to see how well their kidneys are working.
This is important because problems like low potassium or sodium often don’t cause symptoms until they become serious.
Some experts now believe medical guidelines should be updated to reflect these new findings. They say hydrochlorothiazide may be a safer choice for many people, especially those who have a higher risk of kidney disease or diabetes.
If you are currently taking chlorthalidone, don’t stop your medication on your own. Suddenly stopping high blood pressure drugs can be dangerous. Instead, talk to your doctor. They can help you decide if a different medicine might be better for you.
High blood pressure is a serious health issue. If left untreated, it can lead to heart attacks, strokes, and kidney failure. Medicines are important, but they work best when combined with a healthy lifestyle. Eating a balanced diet, exercising regularly, cutting down on salt, and managing stress all help keep blood pressure under control.
This study was led by Dr. George Hripcsak and published in JAMA Internal Medicine. It reminds us that doctors and patients need to think not just about how well a drug works—but also about how safe it is to use long term.
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 How to eat your way to healthy blood pressure and results showing that Modified traditional Chinese cuisine can lower blood pressure.
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