High blood pressure, also known as hypertension, affects millions of people around the world and is one of the leading causes of heart disease and stroke.
In Australia, more than one in three adults live with this condition. Many people take medicine every day to keep their blood pressure under control and lower their risk of serious health problems.
One of the medicines often prescribed is hydrochlorothiazide. This drug belongs to a group of medicines called diuretics, sometimes known as water tablets. It helps the body remove extra salt and water through urine, making it easier for the heart to pump blood and lowering blood pressure.
Although hydrochlorothiazide has been used safely for many years, researchers have been studying whether it may have some unexpected side effects. A new Australian study suggests that people who take this medicine for a long time may have a greater chance of developing certain types of skin cancer. The reason may be that the drug makes the skin more sensitive to sunlight.
The research was led by Dr. Benjamin Daniels from UNSW Sydney and was published in the journal Basic & Clinical Pharmacology & Toxicology. The team examined health records from the Australian Department of Veterans’ Affairs. They focused on adults aged 65 years and older living in New South Wales between 2004 and 2015.
The researchers compared people who had been diagnosed with lip cancer or melanoma with a much larger group of people who did not have these cancers. In total, the study included 45 cases of lip cancer, 659 cases of melanoma, and more than 13,000 people without either disease. They also reviewed the participants’ medicine use and hospital records.
The results showed that people who used hydrochlorothiazide were more likely to develop malignant melanoma, the most dangerous form of skin cancer. The study also found a higher risk of lip cancer, especially among people who had taken the medicine for many years.
Because both cancers are strongly linked with sunlight, the researchers believe the medicine’s effect on sun sensitivity may help explain the findings.
These results do not mean people should stop taking their blood pressure medicine. High blood pressure is a serious condition, and controlling it greatly reduces the risk of heart attacks, strokes, and other health problems. Anyone concerned about their medicine should speak with their doctor before making any changes.
The study does suggest that people taking hydrochlorothiazide should be extra careful in the sun. Wearing sunscreen, using protective clothing and a wide-brimmed hat, and avoiding strong midday sunlight can help reduce skin damage. Doctors may also recommend regular skin checks to look for new or unusual spots.
The findings have already had an impact in Australia. The official product information for hydrochlorothiazide now includes a warning about the possible link between the medicine and skin cancer. Similar findings have also been reported in studies from other countries, adding support to the Australian research.
Scientists say more research is still needed to better understand the size of the risk and whether some patients may benefit from different blood pressure medicines.
For now, the message is simple: keep taking prescribed medicine unless your doctor advises otherwise, protect your skin from the sun, and attend regular health check-ups. These steps can help people gain the benefits of blood pressure treatment while lowering their risk of skin problems.
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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