Many people around the world take medicine to help lower high blood pressure, and one of the most common drugs is called chlorthalidone.
Doctors have trusted this medication for a long time, especially because it helps prevent heart problems. But now, researchers at Columbia University have found that chlorthalidone might not be as safe as we once thought.
High blood pressure, also known as hypertension, happens when the blood pushes too hard against the walls of your arteries. Think of it like too much water pressure in a garden hose—it can cause damage over time. If not treated, high blood pressure can hurt important parts of the body, like your heart, brain, and kidneys.
To treat this, doctors often give medicine and suggest healthy changes in diet and exercise. Chlorthalidone is one type of medicine used for this. It is a water pill, which means it helps the body get rid of extra salt and water. This helps lower the pressure in your blood vessels.
The new study looked at over 730,000 people who were taking medicine for high blood pressure. The researchers followed them for 17 years. They compared chlorthalidone to another water pill called hydrochlorothiazide. Both drugs worked well to lower blood pressure and prevent serious health problems like strokes and heart attacks.
However, the study found something surprising. People who took chlorthalidone were much more likely to have low potassium levels in their blood. This condition is called hypokalemia.
Potassium is an important mineral that helps your muscles, heart, and nerves work properly. When potassium is too low, it can make you feel tired, weak, or cause muscle cramps. In more serious cases, it can even lead to heart problems.
According to the study, 6.3% of people taking chlorthalidone developed low potassium, while only 1.9% of people taking hydrochlorothiazide had this issue. That’s more than three times the risk. The study also found that people on chlorthalidone had more problems with their kidneys and other mineral imbalances in their blood.
This does not mean everyone should stop taking chlorthalidone. Many people use it safely. But it does mean that doctors should check their patients more often if they are using this medicine. Simple blood tests can help make sure potassium levels and kidney function stay healthy.
If you take chlorthalidone and start to feel very tired, weak, or get muscle cramps, you should speak to your doctor. Do not stop the medicine on your own. Your doctor might suggest a different drug or keep a closer eye on your health.
Doctors like chlorthalidone because it stays in the body longer than other drugs and might control blood pressure better. But now, with these new findings, some doctors might think about switching to other options.
It’s also good to remember that medicine is just one part of staying healthy. Eating more fruits and vegetables, cutting back on salt, exercising, and managing stress can all help lower blood pressure. Even small changes in daily habits can make a big difference.
Scientists will keep studying medicines like chlorthalidone to learn more about their long-term effects. This study reminds us that while medicine can help, it’s important to keep checking how it affects the body. Talking openly with your doctor and getting regular checkups can help make sure your treatment is safe and right for you.
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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