A new study from researchers at the University of New South Wales in Sydney has raised concerns about a very commonly used blood pressure medicine called hydrochlorothiazide.
This drug has been prescribed for many years in Australia and around the world to help people control high blood pressure, a condition that affects millions of adults, especially as they get older.
High blood pressure is often called a “silent” problem because it may not cause obvious symptoms at first, but over time it can damage the heart, brain, kidneys, and blood vessels.
For this reason, medicines like hydrochlorothiazide are important and can be life-saving. However, the new findings suggest that this medication may also be linked to a higher risk of certain types of skin cancer, particularly in older adults.
Hydrochlorothiazide works by helping the body get rid of extra salt and water through urine. This reduces the amount of fluid in the blood vessels, which helps lower blood pressure. It has been considered a safe and effective treatment for many people. But scientists have discovered that this drug has what are called “photosensitizing” properties.
This means it can make the skin more sensitive to sunlight. When the skin becomes more sensitive to ultraviolet (UV) radiation from the sun, the risk of damage to skin cells increases. Over time, this damage can lead to changes in the DNA of skin cells, which may increase the risk of developing skin cancer.
In the study, researchers looked at health records from older Australians. They used data from the Department of Veterans’ Affairs, which holds detailed information about medical treatments and diagnoses for many older citizens. The researchers focused on people who had been diagnosed with two types of skin cancer:
lip cancer and malignant melanoma. Malignant melanoma is the most dangerous form of skin cancer because it can spread to other parts of the body if it is not treated early. Lip cancer, although less talked about than melanoma, can also be very serious and can affect a person’s ability to eat, speak, and live comfortably.
After carefully examining the data, the researchers found that people who had taken hydrochlorothiazide were more likely to develop both malignant melanoma and lip cancer compared to those who did not use the drug.
The risk of lip cancer became even higher for people who used hydrochlorothiazide for a long time or in higher amounts over the years. This suggests that the longer someone takes the medicine, the more careful they may need to be about protecting their skin from the sun.
These findings do not mean that everyone who takes hydrochlorothiazide will definitely develop skin cancer. Many factors contribute to a person’s risk, including their skin type, how much time they spend in the sun, whether they use sunscreen, their age, and their family history.
Australia is already a country with very high skin cancer rates because of its strong sunlight and outdoor lifestyle. This means that any factor that further increases sun sensitivity is important to take seriously.
Health experts strongly advise that patients should not stop taking hydrochlorothiazide on their own. Stopping blood pressure medication suddenly can be dangerous and may cause blood pressure to rise quickly.
Instead, patients are encouraged to speak with their doctor or pharmacist if they are concerned. A healthcare professional can assess whether hydrochlorothiazide is still the best option or if another medication might be more suitable.
The study also highlights the importance of regular skin checks. Doctors may suggest that people taking hydrochlorothiazide have their skin examined more often, especially areas that are frequently exposed to the sun, such as the face, lips, ears, scalp, neck, arms, and hands.
Early detection of skin changes can make a big difference in treatment outcomes. When skin cancer is found early, it is often easier to treat and less likely to spread.
In addition, sun protection becomes even more important for people using this medication. Simple habits such as wearing a wide-brimmed hat, using sunscreen with a high SPF, staying in the shade during the strongest sunlight hours, and wearing protective clothing can reduce the risk of sun damage.
These actions are useful for everyone, but especially for those who may have increased sensitivity due to their medication.
In response to this research, the official information provided with medicines that contain hydrochlorothiazide has been updated. This means that doctors and patients can now be better informed about the possible risks and take steps to reduce them.
This study is another reminder that even long-standing and widely used medicines should continue to be carefully studied as new data becomes available.
At the same time, the research does not say that hydrochlorothiazide should no longer be used. It remains an important treatment for high blood pressure and has clear benefits. The key message is balance: understanding both the benefits and the possible risks, and making informed decisions with the help of healthcare professionals.
By staying informed, protecting the skin from the sun, and having regular medical check-ups, patients can continue to manage their blood pressure while also taking care of their long-term skin health.
If you care about high blood pressure, please read studies that early time-restricted eating could help improve blood pressure, and natural coconut sugar could help reduce blood pressure and artery stiffness.
For more health information, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
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