A common drug used to treat high blood pressure may have more side effects than doctors once thought.
Researchers at Columbia University have been studying a medicine called chlorthalidone and found that it could lead to problems like low potassium levels and kidney issues.
High blood pressure, also known as hypertension, happens when the pressure of your blood against your blood vessels is too high. Imagine cars speeding on a highway—if they go too fast, crashes can happen.
In your body, high blood pressure can hurt your blood vessels and lead to serious health issues like heart attacks, strokes, or kidney failure.
To manage high blood pressure, doctors often prescribe medicine. Chlorthalidone is one of those medicines. But researchers wanted to know if it’s really the best option.
They looked at health data from more than 730,000 people who took blood pressure medications over 17 years. They compared chlorthalidone with another drug called hydrochlorothiazide. Both drugs help lower blood pressure and protect against heart attacks and strokes. But chlorthalidone seemed to come with more risks.
People who took chlorthalidone were three times more likely to develop low potassium, a condition called hypokalemia. Around 6.3% of those using chlorthalidone had low potassium, compared to only 1.9% of those on hydrochlorothiazide.
Potassium is a mineral your body needs to help muscles move, nerves work, and your heart beat normally. If potassium levels drop too low, it can make you feel weak or tired and even cause dangerous heart problems.
The study also found that people taking chlorthalidone had a higher chance of other problems. These included changes in electrolytes—important chemicals in your blood that help keep your body working well—and damage to the kidneys.
This doesn’t mean everyone who takes chlorthalidone will get sick. But it does mean doctors may need to check patients more carefully when prescribing it.
For years, many doctors chose chlorthalidone because it seemed better at lowering blood pressure. Now, they might want to think twice, especially if the patient has kidney issues or low potassium levels.
Even if you don’t take medicine, there are natural ways to lower your blood pressure. You can eat healthy foods like fruits, vegetables, and whole grains.
Try to eat less salt. Get regular exercise—just walking 30 minutes a day can help. Avoid alcohol and smoking, and find ways to relax, like listening to music or spending time in nature.
The study from Columbia University helps doctors understand more about how medications affect people. Researchers will keep studying these drugs to make sure they are safe.
If you or someone you know takes chlorthalidone, there’s no need to panic. Just stay informed and talk to your doctor about any side effects. Regular checkups can help catch problems early and keep you healthy.
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