High blood pressure, also known as hypertension, affects more than one-third of Australian adults over 18. If not treated, it can lead to serious problems like heart disease and stroke.
To control blood pressure, doctors often prescribe medicines such as hydrochlorothiazide, one of the most common drugs used in Australia.
But a new study from UNSW Sydney has found something worrying. This common blood pressure drug might increase the risk of skin cancer in older adults. The research showed that people who take hydrochlorothiazide may be more likely to get lip cancer or a serious skin cancer called malignant melanoma.
This might be because hydrochlorothiazide makes the skin more sensitive to sunlight. When the skin is more sensitive, it’s easier to get sun damage, which can lead to cancer.
The study used data from the Department of Veterans’ Affairs in New South Wales. It looked at medical records from 2004 to 2015, focusing on people aged 65 and older who had a healthcare card. The researchers looked at cancer cases, hospital visits, and medicine use over this long period.
They studied the records of 45 people who had lip cancer and 659 people with malignant melanoma. Then they compared those people with a large group of 13,300 people who didn’t have these cancers. The results showed that people who took hydrochlorothiazide had a much higher chance of getting both types of skin cancer.
What’s more, the risk of lip cancer went up the longer someone used hydrochlorothiazide. This means that long-term use of the drug could be more dangerous for older people who need it to control their blood pressure.
Even with these results, the researchers say that no one should stop taking hydrochlorothiazide without talking to their doctor. High blood pressure needs to be treated carefully. Suddenly stopping a medicine like this could cause harm.
Dr. Benjamin Daniels, who led the study, stressed the importance of seeing a doctor before changing any medication. He also said doctors should be aware of this possible risk and take steps to help patients stay safe. For example, patients taking hydrochlorothiazide should have regular skin checks, especially if they’ve been using it for many years.
Doctors may also want to remind patients to practice good sun safety. That means wearing sunscreen, protective clothing, and staying out of the sun during the hottest parts of the day.
Because of this study, the safety information for hydrochlorothiazide has been updated. It now warns doctors about the possible link to skin cancer so they can better protect their patients.
This new Australian research adds to earlier studies from around the world that also found a link between hydrochlorothiazide and skin cancer. It’s a reminder that while medicines help control long-term health problems, they can sometimes come with side effects we didn’t expect.
For patients, this study is a reason to be careful with sun exposure—especially if they take medicines that make the skin more sensitive to the sun. Using sunscreen, wearing a hat, and finding shade can help lower the risk.
The study was published in the journal Basic & Clinical Pharmacology & Toxicology. It offers important new information about the risks linked to one of the most common blood pressure medicines. While treating high blood pressure is important, doctors and patients should work together to make sure the treatment doesn’t increase other risks.
For older adults who have used hydrochlorothiazide for many years, simple steps like skin checks and sun protection can make a big difference in staying healthy.
If you care about skin health, please read studies about top signs of diabetic skin disease, and Mediterranean diet could help lower the skin cancer risk.
For more health information, please see recent studies about eating fish linked to higher risk of skin cancer, and results showing how to combat the effects of aging on your skin.
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