High blood pressure, also called hypertension, is a common health condition in Australia.
It affects more than one in three adults and, if not managed properly, can lead to serious problems like heart disease and strokes.
Many people take daily medication to keep their blood pressure under control. But new research from UNSW Sydney has found that one of the most commonly used drugs for this condition may have an unexpected side effect.
The drug in question is hydrochlorothiazide. It’s a diuretic, which means it helps the body get rid of extra water and salt. This helps lower blood pressure and makes it easier for the heart to work.
However, researchers now believe that this medicine might make the skin more sensitive to sunlight. As a result, people who use hydrochlorothiazide—especially older adults who take it for a long time—may face a higher risk of developing certain kinds of skin cancer.
The study looked at health records from the Department of Veterans’ Affairs. It focused on people aged 65 and older living in New South Wales between 2004 and 2015. The researchers examined cancer diagnoses, hospital visits, and medication use.
They compared people who had been diagnosed with either lip cancer (45 cases) or melanoma (659 cases) to a much larger group of over 13,000 people who did not have these cancers.
They found that those who used hydrochlorothiazide had a higher chance of developing malignant melanoma, which is a dangerous and potentially deadly form of skin cancer.
They also had a higher risk of lip cancer, especially if they had been taking the medication for many years. These types of skin cancer are linked to sun exposure, and since the drug increases sun sensitivity, that might explain the connection.
Even though the study results are concerning, experts say that people should not stop taking their blood pressure medicine without first talking to their doctor. The benefits of controlling high blood pressure are still very important. However, doctors and patients should be aware of the possible risk and take steps to protect the skin from sun damage.
This could include using sunscreen, wearing hats and long sleeves, and staying out of the sun during the middle of the day when UV rays are strongest. Doctors might also choose to check their patients’ skin more often for signs of unusual spots or growths.
Because of this research, the official product information for hydrochlorothiazide in Australia has been updated to warn about the potential link to skin cancer.
The study was led by Dr. Benjamin Daniels and published in the journal Basic & Clinical Pharmacology & Toxicology. It adds to earlier studies from other countries that also suggested a similar connection.
More research is still needed to fully understand how big the risk is and whether other blood pressure medicines might be safer for some people. In the meantime, it’s a good idea for patients to protect their skin and to have regular health checkups to catch any issues early.
If you care about blood pressure, please read studies that new research challenges conventional blood pressure guidelines and scientists make a big breakthrough in high blood pressure treatment.
For more about blood pressure, please read studies that widely used blood pressure drug may increase eye disease risk and common blood pressure drugs linked to cognitive decline.
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