(TNS) — A drug commonly used in treatment for urinary tract infections may carry a risk of cancer, according to a recent study.

The Independent reports that the study from the National Toxicology Program links phenazopyridine hydrochloride to an increased risk of cancer.

“Phenazopyridine hydrochloride is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals,” the report states.

According to The Independent, the drug is frequently used in urinary tract infection medicines, and has been used for decades.

However, it is not approved by the U.S. Food and Drug Administration, and it does generally carry a warning label noting its cancer risks.

The drug was also listed by the New Jersey Department of Health and Senior Service as a hazardous substance in 2001, according to The Independent.