It is also used as a tea, taken a few days before menstruation to aid a suppressed flow. It is used in treatments for clods, upset stomach, and to stimulate blood flow to the pelvis area. It's strong minty smell makes its essential oil useful for externally repelling insects such as mosquitoes, fleas, and flies. It should not be taken or used by pregnant women . Large internal doses have been known to cause convulsions and coma.
Pennyroyal oil is an effective insect repellant.
Pennyroyal placed in a shoe will prevent weariness on long walks and hikes, or journeys. It is also added to protection and exorcism incenses. It aids in making favorable business deals. It is given to arguing couples to cease their fighting and restore harmony in the relationship. It tolerates most soils, and prefers direct sun.