A perennial, glabrous, strongly scented herb.

The herb is the source of true Peppermint Oil. The oil contains menthol (50-55%), menthyl acetate, menthone and small amounts of pinene, phellandrene, l-limonene, terpinene, cadinene, cineole, amyl alcohol, acetic acid, isovaleric acid, acetaldehyde, isovaleric aldehyde and a lactone.

The dried leaves and flowering tops of the plant are official in the U.S. Pharmacopeia under the name Peppermint. The herb is considered aromatic, stimulant, stomachic and carminative, and used for allaying nausea, flatulence and vomiting. Bruised leaves are employed as an external application for relieving local pains and headache. A hot infusion is taken to allay stomach ache and colicky diarrhea. Peppermint is used as an antispasmodic, diuretic, choleretic and carminative and as an expectorant in bronchitis. It is a component in several sedative preparations.