Recurrent UTIs? A gentamicin bladder instillation may be the answer

Another UTI? 

If you find yourself asking this question, know you're not alone: it’s technically called a recurrent urinary tract infection, and there’s a subset of women who get them, unfortunately, on repeat.

“Half of women in their lifetime will have a UTI, which is a quarter of the planet,” said Anne Pelletier Cameron, M.D., a urologist specializing in female pelvic medicine. 

“There’s also 4% of the population who get recurrent UTIs, meaning they have three or more a year.”

If you fall into this category, you've probably already tried several non-antibiotic approaches to avoid them, as well as received your fair share of antibiotics to clear them. 

It may feel as if there's nothing else left to do, but luckily, there is. 

“Women who come to me, who reach this point of needing this type of treatment, are at their wits ends,” said Cameron, who’s nationally sought out by doctors across the country when nothing else seems to be making a dent in the situation.

And the option she's specialized in is extremely effective, says Cameron.

It's called a gentamicin bladder instillation. 

But, before moving to this step, she says basics need to be covered.

“It starts with common sense things like increasing your water intake, making sure your urine is getting properly tested for infection and also making sure there’s no root cause to these UTIs,” said Cameron. 

Typical strategies look like consuming cranberry supplements, using vaginal estrogen cream or prescription methenamine and/or taking preventative antibiotics by mouth. 

But what happens when you've tried all those tactics and you’re still getting infections? 

“This is when a gentamicin bladder instillation comes in handy,” said Cameron. 

Although considered an “off label” use of the drug, meaning the technique with this medication hasn’t been approved by the Food and Drug Administration, it’s been well studied and considered a safe treatment option. 

“Providers can use drugs ‘off label'; it just means the FDA hasn’t studied it for that particular use, but it is an approved drug used elsewhere. And we've seen how effective and life changing it is for people.”

What is a gentamicin bladder instillation? 

Gentamicin is an antibiotic approved by the FDA for intravenous treatment of infections.

For UTI prevention purposes, though, the drug is dissolved into saline and then put into a catheter that you squirt into your bladder.

It's an alternative route for the drug - a bladder wash. It's like mouthwash, she jokes.

“This is a trusted antibiotic that has been used for years, from wound washes to IV treatment for UTIs. It's a great molecule because, when using it as a wash, none of the antibiotic gets absorbed into the body. This is a huge plus given all the concerns and risks associated with antibiotic resistance and overuse.”

The process was created at the University of Michigan, and Cameron’s previous mentor, the late Ed McGuire, M.D., pioneered it. 

Creating the idea in the 1990s, McGuire had several studies on the approach at Michigan, proving its safety and showing that the drug doesn't get absorbed by the body from the bladder, even when left in overnight.

“When I came to Michigan Medicine in the 2000s as a fellow, I said to him ‘why doesn’t anyone else know how to do this? They should!’”

From there, Cameron spearheaded the treatment approach, spreading the word near and far, speaking nationally at conferences, about the effective technique, and also published on it in 2017 and in 2024. 

“Several groups in Europe and in the United States have seen an 80-90% reduction in UTIs using this exact method,” explained Cameron. 

Using gentamicin bladder instillation to treat recurrent UTIs in women

“A woman who can pee on her own gets taught how to catheterize herself and squirt this antibiotic solution into her bladder, usually at night before bed,” said Cameron.

The task may seem onerous, and possibly daunting to some, but Cameron assures that, if you’ve reached this point of agony with recurrent UTIs, you’re willing to try anything. 

And the plus? It doesn’t have significant side effects.

“People are suffering so much that squirting a solution into their bladder before bed seems minimal, and they’re more than willing to try it.”

The solution stays in overnight and is simply peed out once you wake up in the morning.

There are also very few side effects, says Cameron, since the antibiotic isn’t systemically absorbed, meaning it treats the infection locally without entering other areas of the body.

Cameron says her patients first try a gentamicin bladder instillation for three months. 

They then revisit if it’s necessary to continue and discuss how best to proceed if they do.

“I prescribe it for daily use, and then once the UTIs are under control, I recommend spacing it out to every second day, and then from there have them continue to space the wash out until we’re only using it once a week.” 

The other group of patients who benefit greatly from this treatment are those with neurogenic bladder conditions – people who have spinal cord injuries and need to catheterize their bladder to urinate already.

“To them, this isn’t a big deal because they’re already using a catheter which is the hardest part of the process,” said Cameron.

At the University of Michigan, with the Department of Physical Medicine and Rehabilitation, Cameron’s team completed an FDA-supervised trial of patients with neurogenic bladder and recurrent UTIs who were given these same gentamicin instillations to prevent infections. 

“In the study we saw an 83% reduction in UTIs compared to before starting the medication,” said Cameron. 

Asking your doctor about a gentamicin bladder instillation

The American Urologic Association has clear guidelines in place for practitioners on how to treat women with recurrent UTIs. 

There are steps on what to do next if particular approaches fail, but you should always ask questions about the process. 

This approach isn't included in the guidelines yet, but is included in the AUA Guidelines on Neurogenic Bladder.

“All providers typically follow this specific algorithm that has been created, but it’s important you still have a discussion with your provider about the situation and what the treatment goals are,” said Cameron.

Cameron says how grateful patients are after finally finding this solution when everything else has failed, and it’s something that makes her work all the more rewarding.

“I have patients in my office filled with tears and smiles, telling me how they can finally live a full life again without pain from these infections.”

Struggling with recurrent UTIs and want to learn more? Contact U-M's Department of Urology to make an appointment at 734-936-7030.

Sign up for Health Lab newsletters today. Get medical tips from top experts and learn about new scientific discoveries every week.

Sign up for the Health Lab Podcast. Add us wherever you listen to your favorite shows.

Paper cited: “The effects of gentamicin intravesical instillationson decreasing urinary infections in patients with neurogenic bladder after spinal cord injury (GENUIS) trial,” Journal of Urology.