Peppermint essential oil is an energizing oil with a penetrating, minty aroma that helps to relieve both mental and physical fatigue. Use it in the daytime, as its energizing effect may keep you awake at night. Add to a massage blend for digestive problems and flatulence. Peppermint is soothing in a footbath after a long day on your feet, and one drop on a handkerchief is reviving during travel. This is also a great oil to use in a car diffuser for long trips.