Pennyroyal is used to make herbal teas, which, although not proven to be dangerous to healthy adults in small doses, is not recommended, due to its known toxicity to the liver.Consumption can be fatal to infants and children.It has been traditionally employed as an emmenagogue (menstrual flow stimulant) or as an abortifacient. Pennyroyal is also used to settle an upset stomach and to relieve flatulence. The fresh or dried leaves of pennyroyal have also been used when treating colds, influenza, abdominal cramps, and to induce sweating, as well as in the treatment of diseases such as smallpox and tuberculosis, and in promoting latent menstruation. Pennyroyal leaves, both fresh and dried, are especially noted for repelling insects. However, when treating infestations such as fleas, using the plant's essential oil should be avoided due to its toxicity to both humans and animals, even at extremely low levels.