Methenamine Hippurate Versus Trimethoprim in the Prevention of Recurrent UTIs

Several methods are available for use in the prevention of recurrent urinary tract infections (UTIs) over the past few decades. These methods include suppressive antibiotics, estrogen cream, methenamine hippurate, d-mannose, cranberry, probiotics, and vitamin C. Of these, the majority of the literature is in favor of use of suppressive antibiotics for preventing UTIs. However, this data is now about 10 years old. Increasing use of antibiotics over the years has lead to increased resistance of bacteria. In addition, long-term antibiotic use has several adverse effects, some life-threatening. There is recent literature evaluating the use of several of the alternatives to suppressive antibiotics with mixed results. A comparative study of the efficacy of methenamine hippurate to suppressive antibiotics is lacking in the current literature. Several early partly-randomized trials done with methenamine hippurate have shown promising results, but are only as recent as 1987. The primary objective of this prospective, randomized study is to determine whether there is a significant difference in the prevention of recurrent UTIs when given either methenamine hippurate or daily suppressive antibiotics. The secondary objective of this study is to determine how well patients are able to tolerate each of these medications and what adverse effects are observed in a given 1 year time period. The long-term goals of this study are to find an alternative to using suppressive antibiotics, potentially with a lower adverse effect profile and less of the dangers of long term antibiotic use. Finding an alternative to suppressive antibiotics would also tackle the issue of antibiotic resistance.