Last week, startling headlines hit the news. Three commonly prescribed medicines, hydrochlorothiazide, used to treat high blood pressure, voriconazole, an antifungal medicine and tacrolimus, an immunosuppressant were classified as carcinogenic, or cancer causing, to humans. The classification was made by the International Agency for Research on Cancer or IARC, which is the World Health Organization’s cancer research agency.

According to the IARC, there is sufficient evidence that hydrochlorothiazide causes squamous cell carcinoma of the skin and cancer of the lip, as the drug makes the skin more sensitive to ultraviolet radiation. Voriconazole, also has been linked to the same cancers. In the case of Tacrolimus since it suppresses the immune system to prevent rejection of transplanted organs, the reduced immune surveillance may allow abnormal cells to proliferate and it is linked with non-Hodgkin lymphoma with limited evidence for other cancers as well.

These drugs are prescribed to millions of people worldwide. So what happens now?

Guest: Dr. Rajeev Jayadevan convener, research cell, Kerala State IMA and honorary senior consultant gastroenterologist, Sunrise Hospital, Kochi.

Host: Zubeda Hamid

Edited by Sharmada Venkatasubramanian

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Published - August 15, 2026 04:31 pm IST