Over-the-counter drug for condition that 15M women get a year is linked to cancer

As if urinary tract infections weren’t bad enough, a new report claims that a popular over-the-counter drug used to treat UTI symptoms has been linked to cancer concerns.

UTIs are among the most common infections worldwide, affecting some 15 million women a year. Phenazopyridine, sold under brand names such as Azo and Uristat, is used to treat the pain, burning and discomfort associated with UTIs.

But this medication has not been formally approved by the Food and Drug Administration — and research has raised concerns about its potential cancer risk, Bloomberg reported.

Phenazopyridine, first synthesized in 1914, works by numbing the lining of the urinary tract to relieve UTI symptoms.

Bloomberg reported that phenazopyridine was marketed before current FDA regulations for drug approval were in place.

Because of its long history, it was essentially “grandfathered in” and remains on the market without full FDA approval.

One concern about phenazopyridine is that it can mask the symptoms of a UTI, potentially delaying antibiotic treatment.

There are also potential risks associated with high doses or prolonged use.

A 2021 study conducted by the National Institutes of Health (NIH) found that dietary exposure to phenazopyridine caused tumors in two rodent species at two different tissue sites.

In female mice, phenazopyridine caused benign and malignant liver tumors. In rats of both sexes, it caused benign or malignant colorectal tumors. 

The NIH noted that while the animal studies don’t explicitly prove a link between human exposure to phenazopyridine and the development of cancer, the drug is “reasonably anticipated to be a human carcinogen.”

Side effects of phenazopyridine include chest tightness, dizziness, lethargy, loss of appetite and stomach pain.

More severe, though less common, reported reactions include depression, muscle twitching, kidney failure, seizures and nose bleeds. 

In rare cases, phenazopyridine can cause death due to methemoglobinemia, a condition that interferes with the blood’s ability to carry oxygen. 

While phenazopyridine is available OTC in the US, it requires a prescription in Canada and the UK.

UTIs begin when bacteria enter the urethra and infect the urinary tract due to genetic disposition, sexual activity or poor hygiene.

Symptoms include the urgent need to urinate, a burning sensation when peeing, pressure or pain in the lower abdomen or pelvic region, cloudy or blood-tinged urine and urine with a strong odor.

Antibiotics are the primary cure for UTIs as they eliminate the bacteria that cause the infection. However, many patients use phenazopyridine to manage symptoms while they await antibiotics.

Unfortunately, studies indicate that the bacteria that cause UTIs are becoming more resistant to antibiotics, making these infections more dangerous than ever.

Part of this resistance can be attributed to meat consumption, as animals treated with antibiotics can develop resistance to those drugs that’s transferred to humans.

And UTIs seem to be becoming more prevalent. Recent research found the global disease burden of UTIs rose by more than 68% between 1990 and 2019.

Increased rates of UTIs can be attributed to several factors, including a growing population, particularly an elderly one that is more susceptible to UTIs, and a swath of sexually active young people.

But relief may be on the way. In March, the FDA approved the antibiotic Blujepa to treat uncomplicated UTIs in women 12 and older.

The drug acts on a different part of the bacteria compared to most other antibiotics, making it effective against organisms resistant to current treatments.