Does hydrochlorothiazide increase the risk of squamous cell carcinoma (SCC) of the skin?

Bottom Line: Observational data suggest an association between hydrochlorothiazide and the risk of SCC. Causation has not been proven. Risk appears to consistently increase with dose and duration (example: 5 years of use increases risk 3-4 times). Baseline incidence of SCC is <0.1% annually. The same risk has not been established with thiazide-like diuretics (like indapamide or chlorthalidone). The benefit of switching from hydrochlorothiazide to another agent should be weighed against the risk of changing medications. (Reference: “Tools for Practice”)