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ingestible · for uti prevention

Lactobacillus Probiotics

Reviewed by the Nimbera editorial team · Last updated May 2026

Beerepoot and Geerlings (2016, PMID 27092529) review found intravaginal Lactobacillus crispatus in premenopausal women and oral L. rhamnosus GR-1 + L. reuteri RC-14 in postmenopausal women are promising for UTI prevention, though overall RCT results remain inconclusive due to small sample sizes and inconsistent dosing strategies.$25-$45 per month

How to use

Use oral probiotic capsules containing L. rhamnosus GR-1 and L. reuteri RC-14 (minimum 1 billion CFU each) daily, or intravaginal L. crispatus suppositories as directed. Take after any antibiotic course to restore flora.

How it works

Lactobacillus species colonise the vaginal epithelium, produce lactic acid and hydrogen peroxide that lower vaginal pH, and competitively exclude uropathogenic E. coli and other pathogens from ascending the urethra.

Where to buy

Health food stores and pharmacies; look for products specifically containing L. rhamnosus GR-1 and L. reuteri RC-14 (e.g. Fem-Dophilus by Jarrow Formulas). Store in refrigerator.

Typical cost: $25-$45 per month

Safety notes

Not a treatment for active infection. Immunocompromised individuals should consult a doctor before taking probiotics. Strain specificity matters - generic probiotic blends without the researched strains (GR-1/RC-14) have not demonstrated UTI prevention benefit.

Drug & supplement interactions

  • Always tell your doctor or pharmacist about any supplements you take.
  • Interactions can occur with prescription medications, blood thinners, and immunosuppressants.
  • Herbal remedies can affect how the body absorbs or metabolises drugs.
  • Check drugs.com interactions checker before starting.

Clinical source

Beerepoot M, Geerlings S, Non-Antibiotic Prophylaxis for Urinary Tract Infections, Pathogens, 2016

This information is compiled from primary clinical literature and is for informational purposes only. It is not a substitute for professional medical advice. Read our full disclaimer.