A recent study by researchers at Columbia University has brought fresh attention to a common medication used to treat high blood pressure: chlorthalidone.
This drug has been trusted for many years to help lower blood pressure and prevent serious health problems like heart attacks and strokes. But recent findings suggest that it may come with risks that people need to be aware of.
To understand why this matters, it helps to think of your blood vessels as highways and your blood as the cars driving on them. High blood pressure is like speeding—it puts too much pressure on the system and increases the chance of dangerous accidents, such as damage to the heart, kidneys, or brain.
Doctors try to keep blood pressure under control using healthy lifestyle changes and medications. Chlorthalidone is one of those medicines. It works by helping the body get rid of extra salt and water, which lowers blood pressure.
In a large study that looked at health records from over 730,000 people over a span of 17 years, researchers compared chlorthalidone with another similar drug called hydrochlorothiazide. Both medicines are commonly prescribed and are believed to reduce the risk of heart disease.
But when the researchers looked closely, they found that people taking chlorthalidone were more likely to develop a condition called hypokalemia—low levels of potassium in the blood.
Potassium is a mineral that plays a very important role in the body. It helps your muscles work properly, keeps your heart beating normally, and supports your nerves. When potassium levels get too low, people can feel weak, tired, or even experience dangerous changes in their heartbeat.
According to the study, about 6.3% of people taking chlorthalidone had low potassium, compared to only 1.9% of those taking hydrochlorothiazide. That’s more than three times the risk.
In addition to low potassium, people on chlorthalidone also had more problems with other mineral imbalances and kidney function. These side effects don’t happen to everyone, but they are serious enough that people taking this drug should be monitored carefully.
This means checking potassium levels and kidney health regularly through blood tests, especially in the first few months of treatment.
These results don’t mean that chlorthalidone is bad or should never be used. It’s still a useful medicine for many people. But it does show that doctors and patients need to be more careful with it, especially when there are other options available.
If you’re taking chlorthalidone, it’s a good idea to talk to your doctor about your risks and whether this medication is the best choice for you.
Also, it’s important to remember that medication is just one part of treating high blood pressure. A healthy lifestyle can make a big difference.
This includes eating more fruits and vegetables, cutting back on salty foods, getting regular physical activity, limiting alcohol, quitting smoking, and finding ways to reduce stress. These steps can help keep your blood pressure in check and improve your overall health.
In the end, the study from Columbia University is a reminder that even well-known and commonly used medicines need to be studied carefully.
As science continues to evolve, we learn more about how different drugs affect different people. Staying informed, working closely with your doctor, and paying attention to how your body feels are all key to staying safe and healthy while managing high blood pressure.
If you care about blood pressure, please read studies about unhealthy habits that could increase high blood pressure risk, and eating eggs in a healthy diet may reduce risks of diabetes, high blood pressure.
For more information about blood pressure, please see recent studies that early time-restricted eating could help improve blood pressure, and results showing 12 foods that lower blood pressure.
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