Oil of oregano, which is distilled from the flowers and leaves of the oregano plant, could be one of nature's most powerful healer. This natural and versatile oil can be used in multiple ways to help defend you from infection by dangerous bacteria. It is applied to the skin for skin conditions including oily skin, dandruff, canker sores, warts, ringworm, rosacea, and psoriasis, gum disease, toothaches, muscle pain, and varicose veins.. Oil of oregano also contains thymol, an ingredient used in many mouthwashes to combat bacteria, plaque and bad breath. Animal studies suggest that oregano and oregano oil can help fight parasitic infections and reduce infectious diarrhea. It may also affect the digestive ecosystem and alter the stomach's emptying rate.