Can urinating on your feet in the shower cure athlete’s foot?

Dear Cecil: My girlfriend and I have been battling recently over a medical question: Is there benefit to urinating while you’re in the shower? I have long held as “common sense” that peeing in the shower can actually tame (if not cure) common problems like athlete’s foot and other skin fungi. My girlfriend thinks I’m just into some weird fetish. (Maybe it’s because I have better aim while “curing” my foot problems.) More than who’s right, which theory is right? Josh from Chicago

Cecil replies:

Josh, you must be one charismatic hombre if you can get a female human being to associate with you once she’s learned your idea of common sense is peeing on your feet. As for urine’s medicinal properties, let’s put it this way: the most reputable scientific proponent of pee as a cure for athlete’s foot is Madonna (Letterman show, 1994). After that you start getting into some serious flakes.

Urine therapy in various forms has been around since time immemorial. As I’ve discussed before, the stuff is usually pretty sterile and in most cases harmless. Gross though it may sound to normal folk, the oft-cited practice of irrigating battlefield wounds with urine isn’t completely stupid – if the other options are using water of dubious sterility or letting things fester, what the hell. The question is whether it makes any sense if you’ve got a choice of antibacterial or antifungal agents. Instinctive answer: Of course not, nitwit. Diplomatic answer: OK, delete the nitwit part. But Josh, honey bunny, the answer is still no.

Athlete’s foot (tinea pedis) is an irritating condition in which a fungus fond of warm, moist places sets up shop in between your toes. It can cause itching, cracking, and red, scaly skin; sometimes large pieces of skin peel off, leading to secondary infections. To grow and breed, the fungus burrows into the upper layers of skin and feeds on the keratin that keeps your body germ-resistant and watertight. It also causes the basal skin cells to divide more rapidly, making the skin thick and scaly; in severe cases the fungus spreads to the nails, which thicken as well and turn yellow. If you scratch or pick at the affected area, the fungus can travel to other parts of your body, in which case athlete’s foot can become athlete’s pits or athlete’s groin. Because the fungus likes things warm and damp, it survives well in such places as gym showers and locker rooms, and can be easily contracted by walking or standing barefoot thereabouts.

You’re thinking: That rat bastard fungus, I want to piss on its sorry ass. Steady, lad. Athlete’s foot can be hard to cure, so the best thing is to not get it in the first place. Wear flip-flops if you use a communal shower, wash your feet with soap, dry with a clean towel, and put on clean, dry footwear afterward – and if you’re the sweaty type, keep your feet dry with frequent changes of socks and footwear that breathes. If you get infected anyway, the standard over-the-counter treatment is one of those topical antifungal creams or powders you see advertised on TV. The problem with these is they don’t always penetrate deep enough to kill the fungus; in such cases the next line of attack is a prescription oral antifungal agent to attack the fungus from the inside. However, side effects of oral antifungal treatments include liver and heart problems, so try the topical kind first.

With athlete’s foot so tough to lose, you can see why some might give urine a whizz (har!), and in fairness there’s a scrap of sense to the idea. The key isn’t urine itself but a compound in it called urea, which is also an inactive ingredient of many athlete’s foot treatments. Urea is used in skin preparations as an emollient (softener) and exfoliant (flake remover) – it goes after the thickened skin athlete’s foot produces, allowing the fungicide to penetrate and kill the fungus. In fact, because the compound can break down proteins, preparations containing up to 40 percent urea are available to treat nail fungus and even remove toenails nonsurgically, although they take days to work.

So why won’t tinkling on your tootsies help with athlete’s foot? First, there’s not enough urea in urine to do much good – typically only 2 to 2.5 percent. Second, urea per se isn’t what attacks the athlete’s foot fungus; it mainly helps antifungals work. Finally, unless you stopper the tub and let your feet soak, any contact you’d have in the shower would be brief. Again, chances are your quirky shower habits won’t hurt anything, your social life possibly excepted, but I’ll say this – if anybody recommends a topical application of urine for another common dermatological problem, namely acne (think I kid? Googling “acne urine” gets 1.1 million hits), give it a pass.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.