A popular over-the-counter medication used for decades to relieve urinary tract infection (UTI) symptoms has come under scrutiny for a possible link to cancer. Phenazopyridine—commonly sold under brand names such as Pyridium and Safrel—is widely used to ease the burning, discomfort, and irritation caused by UTIs by numbing the lining of the urinary tract.
However, mounting evidence has raised serious concerns about its safety. The National Institutes of Health (NIH) highlighted findings from a 2021 study that showed phenazopyridine caused tumors in two different species of rodents. Female mice developed both benign and malignant liver tumors, while bowel tumors appeared in both male and female rodents.
Although the results stem from animal studies and don’t confirm a direct cancer risk in humans, phenazopyridine is now “reasonably anticipated to be a human carcinogen,” according to the NIH.
The medication is still available over the counter in countries like the UK, though higher doses typically require a prescription. Side effects listed by the Mayo Clinic include dizziness, headaches, chest tightness, and appetite loss. More severe reactions may include seizures, breathing difficulties, and unusual bleeding or bruising.
Rita Jew, president of the Institute for Safe Medication Practices, advises against using the drug. “There is no need for this drug,” she told Bloomberg, raising questions about its continued availability without stronger warnings or restrictions.
Despite the risks, phenazopyridine is still commonly recommended. New York-based gynecologist Dr. Steven Goldstein admitted he wasn’t aware of the cancer-related concerns and has prescribed the medication to patients awaiting UTI test results.
UTIs are highly common, especially among women. In the UK alone, it’s estimated that 1.7 million women suffer from chronic UTIs. The infections typically occur when bacteria—often from the bowel—enter the urinary tract via the urethra. Women are more vulnerable due to their shorter urethra, which allows bacteria quicker access to the bladder.
Factors like sexual activity, certain types of birth control, hygiene habits, and pre-existing health conditions can all increase UTI risk. While antibiotics remain the primary treatment for UTIs, alternative remedies such as methenamine combined with sodium salicylate are being considered safer substitutes to phenazopyridine.
As World No Tobacco Day calls attention to preventable health risks, it’s also a reminder to scrutinize the safety of everyday medications—especially those used so widely and casually.
