Cranberry juice for UTIs?

Jun 15 2011 Published by under Medicine, Uncategorized

I can't seem to stop myself from writing about pee, and I'm not even a nephrologist.  But I deal with pee every day, and many of my younger patients with urinary tract infections will tell me all of the home and herbal remedies they tried before they came to see me.  One of the most common alternative treatments is cranberry juice.  There are several plausible reasons cranberry juice might work against UTIs.

Some studies have shown that cranberry consumption can acidify urine and raise urinary levels of hippuric acid, a compound that can slow bacterial growth. Subsequent studies have found that it is nearly impossible to consume enough cranberry products to significantly change the pH of the urine or to raise concentrations of urine hippuric acid.

Other studies have found that some of the chemicals in cranberry juice can prevent E. coli from adhering to the urinary tract lining.  Since E. coli are the cause of a high percentage of UTIs, this could be significant.  Unfortunately, studies have failed to show significant clinical benefit in several types of UTIs, especially when compared to usual antibiotic therapy.

Adding to our database is a study in the latest issue of Clinical Infectious Diseases. This study looked at preventing recurrent UTIs in young women, a group at significant risk for recurrence.

The results were unimpressive. During the six months of follow up, the cranberry juice group did not have significantly fewer recurrent UTIs than the placebo group.  One caveat to this conclusion is the observation in previous studies that the effect of cranberry is dose-dependent.  In the study, women were given eight ounces of cranberry juice cocktail daily.  It could be argued that this is too little to have an effect.  But to drink, say, 24 oz of low-cal cranberry juice cocktail daily hardly seems like a reasonable trade off.  That's a lot of juice.

For now, I'm not recommending cranberry juice to my patients wishing to prevent UTIs.


Barbosa-Cesnik, C., Brown, M., Buxton, M., Zhang, L., DeBusscher, J., & Foxman, B. (2011). Cranberry Juice Fails to Prevent Recurrent Urinary Tract Infection: Results From a Randomized Placebo-Controlled Trial Clinical Infectious Diseases, 52 (1), 23-30 DOI: 10.1093/cid/ciq073

Raz, R., Chazan, B., & Dan, M. (2004). Cranberry Juice and Urinary Tract Infection Clinical Infectious Diseases, 38 (10), 1413-1419 DOI: 10.1086/386328

15 responses so far

  • DrugMonkey says:

    But..but....cranberry juice cocktail is delicious!

  • LauraA says:

    I have never used cranberry juice cocktail. But I have self treated UTIs with cranberry juice in the past. I drink 8 - 12 oz of straight cranberry juice + lots of water at the first sign of a UTI. If I don't notice improvement the next day then I call the doc and get antibiotics.

    It may all be placebo, I dunno. But it's been effective when I've used it during my last 3 or 4 potential UTIs over the last 5 or 6 years.

    I don't recommend it to other people, but it's a really good first step for me.

  • Peanut says:

    One 8 oz glass cranberry cocktail as the dose? No wonder they didn't find anything! Way too low to be realistic. Here's a case where the docs need to do some interviews to find out what doses real live women use for UTI control/prevention.

    Here's mine when I realize that a UTI is coming on:
    1 L bottle of 50:50 or 75:25 cranberry juice/water in 3 hrs OR 1 L of water in 3 hours, with 2 cranberry capsules/hr. Both options work for me.

    It ain't pleasant, but neither is that horrible burning sensation.

    BTW - 24 oz of fluid is completely reasonable when one is trying to keep the urine dilute enough to reduce irritation.

  • Brushy says:

    Thanks for the post! I usually combine pure Cranberry juice with Juniper berry tea for bladder infections. The Juniper seems to affect a different set of bacteria – making a more effective herbal preparation. Following the directions of Charles Kane's Herbal Medicine-Trends and Traditions book, I’ve found it an excellent resource on the most common herbs and problems they best address – neither overstating nor understating well applied herbal medicine.

  • Vicki says:

    Assuming someone likes cranberry juice anyhow, is there any reason she shouldn't drink large amounts of cranberry juice cocktail rather than iced tea, orange juice, plain seltzer, or other liquids?

    • Dial Doctors says:

      Absolutely not. Make sure to check the nutrition label because juices are notorious for including too much sugar. If the sugar content is low then you're golden.

      Consider diluting your juices gradually so you can increase your H2O intake. Juices, while delicious (oj lover here!), will only lead to more pounds. Water is calorie free

  • Karen says:

    "Assuming someone likes cranberry juice anyhow, is there any reason she shouldn't drink large amounts of cranberry juice cocktail rather than iced tea, orange juice, plain seltzer, or other liquids?"

    Well, it's either a LOT of sugar or sugar substitute.

  • Simon says:

    Mark Crislip wrote quite a thorough post on this on SBM - may be worth adding the link in your post -

    • PalMD says:

      Im somewhat familiar with the blog and with Mark's work. This article is primarily about a new study released July 1. Despite my extended leave, I'm still an editor at SBM.

  • aussie says:

    I agree with peanut! I have also downed over a litre of cranberry juice once, on my 20 min ride to work just so i could go about my day without feeling the need to pee every 10 minutes. I also used to self medicate with a teaspoon of bicarbonate of soda mixed into a tall glass of water. This saved me many times, it was unpleasant but i knew that in 20 min the pain and 'sense of urgency' would be gone. One time when i was taking bicarb the infection was still persisting so i thought i needed antibiotics. The doctor would not believe i had a UTI because the quick test for white blood cells in my urine came up negative. Sure enough, the culture results showed that i had a very low level infection. It appeared my self-medication was perhaps keeping inflammation at bay, rather than killing the bacteria.

  • Uncle Glenny says:

    As peanut says, that dose is a joke. If you've ever tried straight cranberry juice (warning: "tart" is an understatement) you'd realize that the "cocktail" is both quite dilute and highly sweetened.

    It's good however as an additive to other things (e.g. smoothies of various sorts, or mixed drinks).

  • Kipper says:

    I've had good luck with straight cranberry juice (not cocktail) in the past. Whether it just kept me occupied while irritation passed on its own is debatable. It's still 31g of sugar per cup so it's not something I like to get into regularly.

  • soseja says:

    This post is a good example of assumptions not working. And FWIW, an excellent example of why the public doesn't like or 'buy' so-called "science-based medicine."

    The first assumption is that the only way to consume cranberry is as juice in some for or another. But there are dried cranberries, which can be (and are, by some people) eaten out of the hand. And there are softgels, sold for about $10, in which each softgel contains 2 g of cranberry concentrate.

    But the second, and much more dangerous assumption, is that the individual has a urinary tract infection in the first place.

    How do you know? Was there a test -- or more than one test?

    The elderly, and especially those with dementia, seem to have infection-mimic problems and symptoms even without an infection. In that case, a completely different solution would be in order.

    Check your assumptions, folks.

  • Mel says:

    Went to a local doctor for burning while urinating. Ended up being UTI. He gave me 'script for antibiotics. I asked for script for diflucan. Told him I can look at an antibiotic and get a yeast infection. He refused, said more or less that was hogwash. My gyn would have given me one but it was a day his office was closed. Went to pharmacy, instead of getting script filled bought pure cranberry juice, instead. Not cocktail. That's nothing but sugar. By end of day the burning sensation and frequency stopped. Went to gyn next week for follow up just in case juice didn't clear it. Would fill antibiotics and have him give me script for diflucan. But the that test came back negative. The juice worked.