Pennyroyal is a midwives herb. It is a very powerful emmenagogue causing the uterine muscles to contract. It is often combined with other herbs to help stimulate a delayed or irregular menses. In sensitive women it can cause profuse bleeding. Pennyroyal tea and leaf extracts used in proper doses have been used without serious side effects to treat pneumonia, shortness of breath, stomach pains, liver and gallbladder problems. Pennyroyal oil (or high dosing of the herb) however, is highly toxic causing seizures, coma, cardiopulmonary collapse, acute liver and kidney disease and multiorgan failure. Fun fact: Pennyroyal is commonly used as an insecticide to kill mosquitoes and fleas.
Discover Pennyroyal (Bo He You) and other herbs by visiting our Herb Directory.