The Food and Drug Administration (FDA) has recently revised hydrochlorothiazide's labeling to include an increased risk of nonmelanoma skin cancer with drug use. Hydrochlorothiazide is a thiazide diuretic that works in the distal tubule of the kidney to prevent the reabsorption of sodium and chloride ions and promote the loss of water. The drug has been used for many years to treat hypertension.

The FDA based its decision on an examination of case reports submitted to its Sentinel System, a large database dedicated to medical product safety. An associated risk of cancer, mostly squamous cell cancer (SCC), was most prevalent in white patients taking large cumulative doses of hydrochlorothiazide. The revised label states: "The increased risk for SCC in the overall population was approximately 1 additional case per 16,000 patients per year, and for white patients taking a cumulative dose of >= 50,000 mg the risk increase was approximately 1 additional SCC case for every 6,700 patients per year." Hydrochlorothiazide has long been associated with photosensitivity and this has been noted previously in the product's labeling.

Nurses and NPs who work with patients receiving hydrochlorothiazide or products containing hydrochlorothiazide should teach patients to protect their skin by avoiding excessive sunlight and using broad-spectrum sunscreen with a sun protection factor of at least 15, reapplied regularly. Patients should also be taught the importance of regular skin cancer screening. Nurses should remind patients that the risks of sun exposure occur not just in the summer, but year-round.

For complete prescribing information for hydrochlorothiazide, see http://www.accessdata.fda.gov/drugsatfda_docs/label/2020/020504s026lbl.pdf.