In the 28th book of his encyclopaedia “Naturalis Historia”, Pliny describes numerous hypothetical situations where urine can save one’s life. “Bathe the eyes with urine to strengthen them. Apply mixed with an egg-white to sun-burn for two hours; an ostrich egg works best” instructs Pliny, citing Salpe - a famous midwife of the first century BC.
According to Pliny, urine is an irreplaceable substance for removing ink blots, bleaching the teeth, curing baby’s sores, gout, dog bites, skin irritations, burns, diseases of the rectum, chaps upon the body, ulcers of the head, porrigo (disease of the scalp), and cancerous sores. “As to the bite of the scolopendra, the effects of urine are said to be quite marvellous—the person who has been injured has only to touch the crown of his head with a drop of his own urine, and he will experience an instantaneous cure”.
Urine is also a great tool to turn your frown upside down. Apparently, a young boy’s urine mixed with some ashes of burnt cow-dung, when rubbed in your toes, is a useful remedy for melancholy. “They prescribe, also, hare's rennet, to be taken in drink just before the paroxysms come on,” – Pliny adds imperturbably.
It appears that drinking urine was quite of a popular activity back in Pliny's times. Ironically enough, eunuch's urine could save a woman from infertility - must be some sort of premodern vaccination. Drinking the urine of horses, bulls and boars was supposed to awaken sexual energy.
However, improper use of the fluid could lead to quite the opposite consequences. Men should be careful when relieving themselves just anywhere: “If a man makes water upon a dog's urine, he will become disinclined to copulation, they say”.
Lastly, Pliny provides us some food for thought: “A lizard drowned in a man's urine has the effect of an antaphrodisiac upon the person whose urine it is”. Well, hard to disagree. If you catch somebody drowning a lizard in your urine, you might possibly reconsider your ties with this person.