The acid itself is a powerful antiseptic. When administered internally, it causes the appearance of hippuric acid in the urine.
The hippuric acid in the urine acts as a stimulant and disinfectant to the urinary mucous membrane.
The glands secrete hippuric acid which passes from the pericardium into the renal organs.
For this purpose the urine is concentrated and the hippuric acid precipitated by the addition of hydrochloric acid; it is then filtered and boiled for some time with concentrated hydrochloric acid, when it is hydrolysed into benzoic and amido-acetic acid.