A woman's attempt to treat athlete's foot by rubbing it with raw garlic was badly misinformed.  The garlic created a serious contact burn with her foot, according to the BMJ (British Medical Journal). 

The story included comment from Dr. Lisa Maier, a clinical associate professor of dermatology at the University of Washington School of Medicine. Garlic's main chemical agent, diallyl disulfide, can irritate the skin, causing a burn, or cause an allergic contact dermatitis, causing a rash. Better to treat the condition with antifungals, she said.