There is big news about the medicines that are taken to cure diseases. The WHO’s cancer research agency IARC has classified three medicines used in high blood pressure, fungal infections and organ transplantation as Group-1 carcinogens. So what does this mean? Will everyone who takes these medicines get cancer? And should these medicines be stopped immediately? Know the full details…
A report by the World Health Organization’s International Agency for Research on Cancer or IARC has sparked a debate. Three medicines used in high blood pressure, serious fungal infections and organ transplantation—hydrochlorothiazide, voriconazole and tacrolimus—have been classified as Group 1 carcinogens by IARC. The three medicines have been published in Volume 137 of IARC.
Hydrochlorothiazide is a thiazide diuretic used primarily to treat high blood pressure and fluid retention. Voriconazole is used to treat or prevent serious fungal infections, especially invasive aspergillosis. Tacrolimus is used as an immunosuppressive drug to prevent the body from rejecting new organs after organ transplantation.
However, the term Group 1 is important to understand here. The IARC Group 1 classification means that there is sufficient scientific evidence of a link to cancer in humans. It does not mean that everyone who takes the medicine will develop cancer. The IARC rating reviews evidence from epidemiological studies, animal experiments and mechanistic studies.
Regarding hydrochlorothiazide, the IARC said that there is sufficient evidence of a link between its use and squamous cell carcinoma of the skin and lip cancer. The medicine may react with ultraviolet radiation to cause phototoxicity. For voriconazole, there is also sufficient evidence of an association with squamous cell carcinoma of the skin, especially with ultraviolet radiation. Similarly, for tacrolimus, IARC said there is sufficient evidence of an association with non-Hodgkin lymphoma and post-transplant lymphoproliferative disorder in humans. IARC also noted that the evidence for its association with leukemia and squamous cell carcinoma of the skin is limited.
However, patients should not be alarmed by this report. It is not advisable to stop these medications suddenly without expert advice. Especially stopping high blood pressure medications on their own can lead to other health problems. Therefore, people taking medications should consult their doctor before proceeding. People taking hydrochlorothiazide should be especially vigilant about skin protection if they are exposed to sunlight for a long time. It is better to seek the advice of a dermatologist if you notice new spots, sores, moles or unusual growths on the skin. Most importantly, IARC’s Group 1 classification is not a directive to immediately stop taking the medication. Doctors will make treatment decisions based on the patient’s benefits, potential risks, and individual health status.
