FREAKY PHARMA –
May 27, 2025 – Used for urinary tract infections Azo, Pyridium, Prodium, Pyridiate, Baridium, and Uricalm — available over the counter (OTC) in the US and UK at lower strengths and by prescription at higher strengths. Experts are warning the drug could cause cancer based on early evidence from animal studies. n one study conducted by the National Institutes for Health (NIH), it was found that dietary exposure to phenazopyridine caused tumors in two rodent species at two different tissue sites.
In female mice, it caused benign and malignant liver tumors while in rats of both sexes, it caused benign or malignant colorectal tumors.
The government agency noted that while the animal studies don’t prove a direct link between human cancer and exposure to phenazopyridine, it is ‘reasonably anticipated to be a human carcinogen.’
Experts say these findings are troubling, especially as phenazopyridine doesn’t require a prescription in the US as it does in many other parts of the world, including the UK and Canada.
