High blood pressure, or hypertension, is a very common health problem in Australia. It affects more than one-third of adults aged 18 and older. If it’s not managed well, it can lead to serious health problems like heart attacks and strokes.
To help control high blood pressure, doctors often prescribe medications. One of the most commonly used drugs in Australia is hydrochlorothiazide. However, a new study from UNSW Sydney has found a potential risk linked to this medicine: it may raise the chances of developing skin cancer, especially in older adults.
This finding is worrying because hydrochlorothiazide can make the skin more sensitive to sunlight. When skin becomes extra sensitive to the sun, it’s easier for sun damage to occur, which can lead to skin cancer over time.
The researchers studied data from the Department of Veterans’ Affairs (DVA), which included anonymous information about cancer cases, hospital visits, and medicine use among people aged 65 and older living in New South Wales. The study covered the years from 2004 to 2015.
They looked at two groups: people who were diagnosed with skin cancers (45 cases of lip cancer and 659 cases of malignant melanoma) and a much larger group of 13,300 people who did not have these cancers.
The results showed that people taking hydrochlorothiazide had a higher risk of getting both malignant melanoma and squamous cell lip cancer. Even more concerning, the risk of lip cancer increased the longer someone had been using the drug. This means the longer people stayed on hydrochlorothiazide, the higher their chances of developing this type of cancer.
Despite the findings, the researchers strongly advise against suddenly stopping the medication. High blood pressure must still be treated because it can lead to life-threatening problems if ignored. Stopping a blood pressure medicine without a doctor’s advice can be dangerous.
Instead, the study recommends that doctors and patients work together to manage the risks. Doctors could perform regular skin checks on patients who are taking hydrochlorothiazide and remind them to be careful about sun exposure. Simple steps like wearing sunscreen, putting on protective clothing, and staying out of the sun during peak hours can help lower the risk.
Because of this study, the official prescribing information for hydrochlorothiazide has been updated to warn about the possible risk of skin cancer. This update helps ensure that doctors are aware and can take precautions to keep their patients safe.
This research also matches findings from other studies around the world, which have suggested a similar link between hydrochlorothiazide and skin cancer. It highlights the importance of not only focusing on the benefits of controlling blood pressure but also paying attention to the possible long-term side effects of medications.
For patients, this study is a reminder to practice good sun safety, especially if they are taking medicines that can make their skin more sensitive to the sun.
The study was led by Dr. Benjamin Daniels and his team and was published in the journal Basic & Clinical Pharmacology & Toxicology. It adds important new knowledge about how commonly used drugs can have effects beyond their main purpose.
Managing conditions like hypertension is still very important, but it’s equally important to think about a patient’s overall health, including their risk of developing other serious conditions like skin cancer.
If you care about blood pressure, please read studies about how diets could help lower high blood pressure, and 3 grams of omega-3s a day keep high blood pressure at bay.
For more health information, please see recent studies about how tea and coffee influence your risk of high blood pressure, and results showing this olive oil could reduce blood pressure in healthy people.
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