Peppermint leaf and oil (2-4 drops in a cup of warm water, mixed well) are used to counteract nausea and vomiting and to relieve intestinal gas and bowel irritation. Peppermint is also used for biliary disorders, dyspepsia, headache, and fevers and colds. In Europe enteric-coated capsules of peppermint oil are taken for colitis and irritable bowel syndrome. In Chinese medicine peppermint is indicated for fever and headaches associated with certain kinds of colds and flu (wind-heat, with yellow or green mucus and fever), and skin lesions.

A classic European cold and flu remedy is made by making a strong infusion with 1 part each of peppermint herb, yarrow tops, and elder flowers and drinking 1-2 cups hot. Take a hot bath during the time the tea is consumed, wrap up in a sheet, and cover yourself with a sleeping bag—then sweat. This sweating therapy is good for breaking a fever (diaphoretic), releasing heat and toxins from the body. Make sure to replace lost liquids with plenty of herb tea or water.