High blood pressure, also known as hypertension, is a very common health problem in Australia and around the world. It often develops slowly and may not cause any clear symptoms at first.
Many people do not even know they have it until they have a health check. However, if high blood pressure is not treated properly, it can damage the heart and blood vessels over time.
This can lead to serious conditions such as heart disease, stroke, and kidney problems. Because of these risks, many people need to take daily medication to control their blood pressure and stay healthy.
One of the most widely used medicines for this purpose is called hydrochlorothiazide. This drug belongs to a group of medicines known as diuretics, sometimes called “water tablets.” These medicines help the body remove extra salt and water through urine.
By reducing the amount of fluid in the body, they lower blood pressure and make it easier for the heart to pump blood. Hydrochlorothiazide has been used for many years and is generally considered safe and effective.
However, new research from UNSW Sydney has raised concerns about a possible side effect of this medication. The study suggests that hydrochlorothiazide may make the skin more sensitive to sunlight.
This means that people taking the drug could be more easily harmed by ultraviolet (UV) rays from the sun. Over time, this increased sensitivity may raise the risk of developing certain types of skin cancer.
The researchers used health data from the Department of Veterans’ Affairs in Australia. They focused on people aged 65 and older who were living in New South Wales between 2004 and 2015. This group was chosen because older adults are more likely to take blood pressure medication and may already have higher exposure to sunlight over their lifetime.
In the study, the researchers looked at people who had been diagnosed with skin cancers, including lip cancer and malignant melanoma. Malignant melanoma is a serious form of skin cancer that can spread to other parts of the body and become life-threatening.
The study included 45 cases of lip cancer and 659 cases of melanoma. These patients were compared with a much larger group of more than 13,000 people who did not have these cancers.
After carefully examining medication records and health outcomes, the researchers found a clear pattern. People who had used hydrochlorothiazide were more likely to develop malignant melanoma than those who had not used the drug.
They also found an increased risk of lip cancer, especially among people who had taken the medication for a long time. Both melanoma and lip cancer are strongly linked to sun exposure, which supports the idea that increased sun sensitivity caused by the drug may play a role.
Even though these findings may sound worrying, health experts stress that patients should not stop taking their medication without medical advice. High blood pressure itself is a serious condition, and controlling it remains very important. For most people, the benefits of taking blood pressure medicine are still greater than the potential risks.
Instead, doctors and patients should be aware of this possible side effect and take simple steps to reduce risk. Protecting the skin from the sun is very important.
This can include using sunscreen, wearing protective clothing such as hats and long sleeves, and avoiding strong sunlight during the middle of the day. Regular skin checks can also help detect any unusual changes early.
Because of this research, the official product information for hydrochlorothiazide in Australia has been updated to include a warning about the possible link to skin cancer. This helps both doctors and patients make more informed decisions about treatment.
The study was led by Dr. Benjamin Daniels and was published in the journal Basic & Clinical Pharmacology & Toxicology. It adds to earlier research from other countries that has reported similar findings. Scientists are continuing to study this issue to better understand how large the risk is and whether other medications may be safer options for some people.
For now, the key message is balance. People should continue managing their blood pressure carefully while also taking steps to protect their skin. Regular check-ups and simple daily precautions can make a big difference in staying healthy over the long term.
If you care about high blood pressure, please read studies about unhealthy habits that may increase high blood pressure risk, and drinking green tea could help lower blood pressure.
For more information about high blood pressure, please see recent studies about what to eat or to avoid for high blood pressure, and 12 foods that lower blood pressure.
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