Table 1 Baseline characteristics of included studies
Study | RCT type | Language | Patients enrolled (N), Methenamine/Control | Groups, Methenamine/Control | Mean age—years, Methenamine/Control | Symptomatic UTI episodes (N)—Methenamine/Control | Positive urine culture (N)—Methenamine/Control | Asymptomatic bacteriuria after 6 or 12 months (N)—Methenamine/Control | Adverse effects, Methenamine/Control | Methenamine hippurate dosage | Antibiotic used and dose | Duration of follow-up |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Botros, 2022 [13] | Two arm, parallel | English | 43/43 | Methenamine/Antibiotic | 73.2 ± 10.5 / 70.6 ± 15.0 | 28/28 | NS/NS | NS/NS | 4/6 | 1 g twice daily | Oral Trimethropim, 100 mg once nightly | 12 months |
Brumfitt, 1983 [14] | Three arm, parallel | English | 25/20 | Methenamine/Antibiotic | 38.2 ± 18/39.9 ± 20.5 | 18/11 | 10/8 | NS/NS | 7 (gastrointestinal intolerance and rash of vagina)/1 (rash of vulva or vagina) | 2000 mg, daily | Oral Trimethropim, 100 mg | 12 months |
Chu, 2016 [15] | Two arm, parallel | English | 45/40 | Methenamine/Antibiotic | 62.2 ± 10.04 /61.5 ± 12.1 | 0/2 | 1/4 | 1/2 | NS/NS | 1 g, two doses (daily) | 500 mg ciprofloxacino | 3 weeks |
Gundersen, 1986 [17] | Two arm, parallel | English | 15/15 | Methenamine/Placebo | 74.5 ± NS / 74 ± NS | NS/NS | NS/NS | 8/4 | 1/1 | 1 tablet (dose NS), twice daily | NS | 6 months |
Harding, 2022 [16] | Two arm, pragmatic | English | 103/102 | Methenamine/Antibiotic | 49.9 (19.1) / 50.3 (18.1) | 59/47 | 54/42 | 44/22 | 82/83 | 1 g twice daily | 50/100 mg of nitrofurantoin, 100 mg of trimethoprim or 250 mg of cefalexin | 12 months |