High blood pressure, also known as hypertension, is one of the most common health problems in Australia and around the world. More than one in three Australian adults live with this condition.
High blood pressure often develops quietly and may not cause obvious symptoms for many years. However, if it is left untreated, it can damage blood vessels and important organs throughout the body.
Over time, uncontrolled high blood pressure can lead to serious health problems, including heart attacks, strokes, heart failure, kidney disease, and vision problems. Because of these risks, millions of people take medicines every day to keep their blood pressure under control.
One of the medicines commonly used to treat high blood pressure is hydrochlorothiazide. This drug belongs to a group of medicines called diuretics, sometimes known as “water pills.” It helps the body remove extra salt and water through urine, which lowers blood pressure and reduces strain on the heart and blood vessels.
Hydrochlorothiazide has been widely used for many years because it is generally effective and inexpensive. However, new research from UNSW Sydney suggests that the medicine may have an unexpected side effect. According to the study, taking hydrochlorothiazide may increase the risk of developing certain types of skin cancer, especially in older adults.
The study was led by Dr. Benjamin Daniels and was published in the journal Basic & Clinical Pharmacology & Toxicology.
Scientists became interested in this question because hydrochlorothiazide can make the skin more sensitive to sunlight. Australia has some of the highest rates of skin cancer in the world due to its strong ultraviolet radiation and outdoor lifestyle. If a medicine increases sensitivity to sunlight, it may potentially raise the risk of skin damage and cancer over time.
To investigate this possibility, the researchers examined health records from the Australian Department of Veterans’ Affairs. They focused on people aged 65 years and older who lived in New South Wales. The study used information collected between 2004 and 2015, including records of cancer diagnoses, hospital admissions, and prescription medications.
The researchers identified people who had developed two types of skin cancer. One group included 45 people who were diagnosed with lip cancer.
The second group included 659 people who developed malignant melanoma, one of the most dangerous forms of skin cancer because it can spread to other parts of the body. These patients were then compared with more than 13,000 people who did not have these cancers.
The results showed that people taking hydrochlorothiazide had a higher likelihood of developing these forms of skin cancer. The researchers also discovered that the risk of lip cancer increased the longer a person used the medicine. This finding suggests that long-term exposure to the drug may have a cumulative effect on the skin.
The study’s findings are consistent with results from previous research conducted in other countries. Together, these studies suggest that there may be a real link between hydrochlorothiazide use and certain types of skin cancer.
However, the researchers stressed that there is no reason for patients to panic. High blood pressure is itself a serious medical condition that requires treatment. Stopping medication suddenly without medical advice could increase the risk of heart attack, stroke, and other dangerous complications.
Instead of discontinuing the medicine, the researchers suggest that doctors and patients should take practical steps to reduce potential risks. Doctors may consider performing regular skin examinations for patients who take hydrochlorothiazide, especially those who have been using it for many years.
Patients can also protect themselves from excessive sun exposure. Using sunscreen, wearing wide-brimmed hats and protective clothing, seeking shade, and avoiding the strongest sunlight during the middle of the day can all help reduce the risk of skin damage.
To ensure that healthcare professionals are aware of these findings, the safety information that accompanies hydrochlorothiazide has been updated. This allows doctors to discuss the possible risks and benefits with their patients and make informed decisions based on each person’s medical history and risk factors.
The researchers say the findings highlight the importance of carefully balancing the benefits of controlling high blood pressure against the possibility of side effects. The study does not suggest that hydrochlorothiazide should no longer be used.
Instead, it provides valuable information that can help doctors monitor patients more closely and encourage good sun protection habits.
As scientists continue to learn more about the long-term effects of commonly used medicines, studies like this can help improve patient safety and allow people to make better-informed choices about their healthcare.
If you care about high blood pressure, please read studies about breakfast for better blood pressure management, and the gut feeling that lowers blood pressure.
For more health information, please see recent studies about how the dash diet helps lower blood pressure, and how to eat your way to healthy blood pressure.
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