pennyroyal

plant

Also known as: Mentha pulegium

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Last updated

July 23, 2026

Quick Summary

Pennyroyal refers to several low-growing, aromatic herbs belonging to the mint family, Labiatae. Two primary species are recognized:1

European Pennyroyal (Mentha pulegium): A perennial mint with small, aromatic leaves.2
American Pennyroyal (Hedeoma pulegioides): A North American mint known for its blue or violet flowers. Its oil has been used in folk medicine and as a mosquito repellent.23

The name "pennyroyal" may stem from Anglo-French terms related to "royal pennyroyal". Other related plants include "false pennyroyal" (Trichostema brachiatus), which has sticky leaves and blue flowers.24

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mint
Major species
Pennyroyal (M. pulegium) has small oval obtuse leaves and flowers in axillary whorls and is remarkable for its creeping habit and pungent odor. It has been used in folk medicine to induce perspiration and menstruation. The plant has also been used as an herbal abortifacient,…
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Pennyroyal (M. pulegium) has small oval obtuse leaves and flowers in axillary whorls and is remarkable for its creeping habit and pungent odor. It has been used in folk medicine to induce perspiration and menstruation. The plant has also been used as an herbal abortifacient,…
Read More