High blood pressure, or hypertension, is a serious condition that affects millions of people worldwide. It happens when the force of your blood pushing against the walls of your blood vessels is too strong.
Over time, this extra pressure can damage the heart, brain, and kidneys, leading to heart attacks, strokes, and other major health issues. To keep blood pressure under control, doctors often prescribe medications—one of which is called chlorthalidone.
Chlorthalidone is a pill commonly given to help lower blood pressure. It works by helping the body get rid of extra salt and water, which reduces the pressure inside blood vessels. But a new study from Columbia University has found that this drug might come with some risks that patients and doctors need to watch closely.
Before we look at the study’s results, it’s helpful to understand how medications like chlorthalidone are used. There are different types of blood pressure pills, and two of the most common ones in the same group are chlorthalidone and hydrochlorothiazide.
Both are used to reduce blood pressure and protect the heart and blood vessels, and both have been in use for many years.
In this study, researchers examined the health records of over 730,000 people who took these blood pressure medications over a period of 17 years. Their goal was to compare the side effects of chlorthalidone and hydrochlorothiazide to see if one drug caused more problems than the other.
The results showed that people taking chlorthalidone were nearly three times more likely to develop low potassium levels, a condition known as hypokalemia. Potassium is a key mineral that helps your heart beat regularly and supports healthy muscles and nerves.
When potassium levels drop too low, people can feel weak, tired, or even develop irregular heart rhythms. In the study, 6.3% of people on chlorthalidone had this issue, compared to just 1.9% of those on hydrochlorothiazide.
In addition to the potassium problem, those on chlorthalidone also had more trouble with their electrolytes, which are tiny but important chemicals in the body that help control heartbeat and muscle movement.
The researchers also found that this drug was more often linked to kidney issues—an important concern because our kidneys filter waste and keep the body’s fluids balanced. If the kidneys are affected, it can lead to bigger health problems over time.
While these findings may sound concerning, it’s important to remember that not everyone will have these side effects. Many people take chlorthalidone without any problems.
But the study does raise questions about whether chlorthalidone should always be the first choice for blood pressure treatment, especially since hydrochlorothiazide seemed to cause fewer issues in this large group of patients.
Doctors may now start to take a closer look at which drug they recommend, based on each person’s health situation.
For people who are already on chlorthalidone, this doesn’t mean they need to stop taking it—but it does mean that regular doctor visits and blood tests are especially important. These check-ups can help catch any problems with potassium levels or kidney function early on, before they become serious.
Of course, medication is just one part of managing high blood pressure. There are many other ways to help keep it under control. Eating a healthy diet with lots of fruits and vegetables, and cutting back on salt, can make a big difference.
So can regular physical activity, avoiding too much alcohol, quitting smoking, and finding ways to manage stress—such as through breathing exercises, yoga, or spending time in nature.
In the end, this study reminds us that every medicine has its pros and cons. The best approach is to stay informed, talk openly with your doctor, and make decisions together about what’s best for your health. With the right care and attention, it’s possible to keep your blood pressure in a healthy range and live a longer, healthier life.
If you care about high blood pressure, please read studies about potatoes and high blood pressure, and top 10 choices for a blood pressure-friendly diet
For more information about high blood pressure, please see recent studies about impact of vitamins on high blood pressure you need to know, and the powerful link between high blood pressure and a potassium-rich diet.
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