A major study has revealed new insights into the safety of two common drugs used to treat high blood pressure: chlorthalidone and hydrochlorothiazide.
The study lasted 17 years and included more than 730,000 patients. It was conducted by researchers at Columbia University and published in JAMA Internal Medicine.
Both of these medications are prescribed to lower blood pressure and reduce the risk of heart attacks, strokes, and heart failure. They are part of a group of drugs called diuretics, or “water pills,” that help the body get rid of excess salt and water.
While both drugs are effective, the study found that chlorthalidone may carry more risks than hydrochlorothiazide. One of the main concerns is hypokalemia, a condition caused by low potassium levels in the blood. Potassium is important for keeping the heart and muscles working properly.
In the study, 6.3% of patients taking chlorthalidone developed hypokalemia. That’s nearly three times more than the 1.9% of patients who had this issue while taking hydrochlorothiazide. Low potassium can cause dangerous heart rhythm problems, confusion, and even kidney failure. It can also raise the risk of developing type 2 diabetes.
The study also found that chlorthalidone was linked to other side effects, including problems with kidney function and imbalances in important minerals in the blood. These problems were seen even at lower doses of the drug, which makes the findings even more serious.
Because of these results, some doctors and health experts are now questioning whether chlorthalidone should remain a top choice for treating high blood pressure.
The findings suggest that healthcare providers may need to monitor patients more closely when prescribing chlorthalidone—or choose a safer alternative like hydrochlorothiazide.
Managing high blood pressure is very important because the condition affects millions of people and can lead to severe health problems if not treated well.
Treatment usually includes a mix of medications and healthy lifestyle changes, like eating nutritious foods, exercising regularly, avoiding too much alcohol, quitting smoking, and reducing stress.
It’s also important for people with high blood pressure to check their blood pressure at home and see their doctor regularly. This helps ensure that their treatment is working and that any side effects can be spotted early.
This study highlights how important it is to choose the right medication. Chlorthalidone works, but it may come with greater risks. Hydrochlorothiazide, which has a lower chance of causing serious side effects, might be a better option for some patients.
The research, led by Dr. George Hripcsak, shows how important it is to keep studying medications so doctors can make the best choices for their patients. It reminds both patients and doctors that blood pressure treatment is not one-size-fits-all. Personalized care and attention to side effects can make a big difference.
If you care about blood pressure, please read studies about This alcohol treatment could help treat high blood pressure and How blood pressure changes with age.
For more about blood pressure, please read studies about Intensive blood pressure treatment for older adults may harm heart and kidneys and What you should know about high blood pressure medications.
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