• Increase fluid intake by ~1.5 L/day if baseline intake <1.5 L → RCT showed reduced UTI episodes & less antibiotic use over 12 months
• Timed voiding; avoid prolonged holding of urine
• Post-coital voiding
• Avoid spermicides and occlusive underwear
• Manage constipation
• Optimise diabetes control (consider checking HbA1c)
• Address incomplete emptying (double-voiding, BPH management, intermittent self-catheterisation (ISC) if necessary)

1. Vaginal Oestrogen (Post-Menopausal Women)

Strong evidence for reducing rUTIs.

• Estriol 0.5 mg cream (e.g., Ovestin): Loading 0.5 mg once daily for 2 weeks; Maintenance 0.5 mg 2–3 times per week
• Estradiol vaginal tablet (Vagifem 10 µg): Loading 10 µg once at night for 2 weeks; Maintenance 10 µg twice weekly
• Estradiol pessary (Imvaggis 30 µg): Daily × 2 weeks → every 2–3 days for maintenance

2. Methenamine Hippurate (Hiprex)

Dose: 1 g twice daily.

Requires acidic urine (pH <5.5) → can add vitamin C 500 mg once–twice daily.

Avoid in severe renal impairment or dehydration. Supported by RCTs including ALTAR trial (non-inferior to antibiotics).

3. D-Mannose

Earlier small trials suggested benefit; more recent large RCT did not show a significant reduction in primary care rUTI rates. Overall judged weak/contradictory evidence.

• Maintenance: 1–2 g once daily
• High-risk times: 1–2 g twice daily
• At onset of symptoms: 1.5–2 g 2–3×/day for 48 hrs, then once daily for 3–5 days

4. Cranberry Extract

Standardised products (PAC ≥36 mg/day) may reduce recurrence. Evidence inconsistent – Systematic reviews/meta-analyses show mixed results; some benefit with high-standardised proanthocyanidin extracts, but overall evidence is contradictory.

5. Probiotics (Lactobacillus spp.)

Weak evidence, not usually prescribed; may benefit women with dysbiosis or after antibiotics.

6. Immunoactive Prophylaxis (Uro-Vaxom (OM-89))

A bacterial lysate vaccine derived from 18 strains of E. coli. It works by up-regulating innate immunity and reducing susceptibility to new infections.

Dose: One capsule daily for 3 months (most evidence-based regimen)

Evidence:

• Meta-analysis (~2,800 patients): significant reduction in recurrence, NNT ≈ 6.
• Improves cystitis-free intervals (~50% of patients remain cystitis free at 6-12 months vs placebo)
• EAU: evidence promising but heterogeneous → weak recommendation
• Particularly helpful in patients wanting to avoid antibiotics

Safety:

• Very well tolerated; mild GI upset occasionally
• No systemic safety concerns in trials
• Safe in long-term follow-up studies

GAG Layer Replacement (Hyaluronic Acid ± Chondroitin Sulphate)

Meta-analyses: reduced recurrence + longer recurrence-free period + symptom improvements. Regimen: weekly × 4–6 → monthly × 3–6

Intravesical Gentamicin

For refractory multidrug-resistant rUTI. Mostly in neurogenic bladder. Specialist-only.

Use only after lifestyle + non-antibiotic options have been exhausted.

General Principles:

• Follow local antimicrobial stewardship policies
• Choose agent based on local resistance + culture sensitivities

Options include:

• Continuous nightly prophylaxis
• Intermittent/rotational prophylaxis
• Self-start therapy (3-day course at onset of typical symptoms)
• Self-diagnosis and self-treatment with short-course antibiotics is safe and effective in compliant women
• Post-coital prophylaxis – For clear intercourse-related rUTIs.
  • Take within 2 hours after intercourse. Examples (exact agent depends on local antimicrobial guidance): Nitrofurantoin 100 mg, Trimethoprim 200 mg, Cefalexin 500 mg, Fosfomycin 3 g (used in some regions)