Organic acids have been used successfully in the treatment of infections of the urinary tract since the introduction of the ketogenic diet by Clark1 and Helmholz2 in 1931. The bacteriostatic factor in this method of treatment has been shown to be betahydroxybutyric acid.3 However, the complete oxidation of this substance, when taken orally by the nondiabetic subject, precluded its use in the efforts to replace the cumbersome and difficultly enforcible ketogenic regimen.4 It remained for Rosenheim5 to introduce mandelic acid, a nontoxic organic acid, which passes unchanged from the gastrointestinal system to the urinary tract. Its high urinary bacteriostatic property for certain infections, especially those caused by Bacillus coli and by Streptococcus faecalis in the presence of strongly acid urine (ph 5.5 or less) has been amply confirmed by numerous investigators.6
A sufficient quantity of the drug must be given to maintain a