Label changes coming to hydrochlorothiazide to warn about non-melanoma risk

In late August, FDA approved labeling changes on hydrochlorothiazide (HCTZ) to inform clinicians and patients about a small risk of developing non-melanoma skin cancer—basal cell skin cancer or squamous cell skin cancer—associated with the use of HCTZ. At the same time, FDA is encouraging patients to protect their skin from the sun.

Specifically, the labeling changes will include the following:

  • Adverse Reactions, Postmarketing Experience: Information has been added about an increased risk of non-melanoma skin cancer associated with HCTZ.
  • Patient Counseling Information: Information has been added instructing patients to protect their skin from the sun and undergo regular skin cancer screenings.

FDA based the changes on recent evidence, specifically an FDA Sentinel Initiative study, which found an increased risk for squamous cell carcinoma in patients taking HCTZ. In the overall study population, the risk was one additional case per 16,000 patients per year.

In a statement, FDA said the “increased risk of developing non-melanoma skin cancer while taking HCTZ, a drug associated with photosensitivity (increased sensitivity to sunlight), is small.”

In addition, FDA noted that the treatment for non-melanoma skin cancer is typically successful, but the risks of uncontrolled blood pressure can be severe and include life-threatening heart attacks or stroke.

“Given this information, patients should continue to use HCTZ and take protective skin care measures to reduce their risk of non-melanoma skin cancer, unless directed otherwise from their health care provider,” the agency stated.

HCTZ is one of the most commonly prescribed drugs in the United States, with an estimated 10 million patients using the drug each year for conditions such as hypertension and diabetes.