A food-derived sugar used mainly as a non-antibiotic option to help prevent and ease recurring bladder infections by coating the bacteria so they cannot stick to the bladder. Evidence is genuinely mixed: early studies were encouraging, but larger recent trials found no clear benefit. Safety is excellent; main downside is mild loose stools. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Urine culture (during symptoms) | No growth when asymptomatic; E. coli during infection | Confirms recurrences are mannose-sensitive E. coli, the only target D-Mannose addresses |
| Urinalysis (leukocytes, nitrites) | Negative for nitrites and leukocyte esterase when well | Screens for active infection and tracks symptomatic episodes |
| eGFR | >90 mL/min/1.73m² (≥60 generally adequate) | Establishes kidney function given D-Mannose is renally cleared |
| Fasting glucose / HbA1c | Fasting 70–90 mg/dL; HbA1c <5.4% | Reassurance in diabetics that a sugar supplement is not affecting control |
Cadence: Review at 3 and 6 months of preventive use, then every 6–12 months if continued