Pennyroyal (Mentha pulegium or Hedeoma pulegioides) has a long history of traditional use in folk medicine, particularly for women's health issues, including menstrual complaints. In the context of PMS Type P (which refers to the "Pain" or "Physical" subtype, characterized by cramps, bloating, and other physical symptoms), pennyroyal was historically used as an emmenagogue to stimulate menstruation and purportedly relieve menstrual discomfort.

Traditional herbal texts from both European and North American sources mention pennyroyal as a remedy for suppressed menstruation, menstrual cramps, and to "bring on" periods. However, these uses are rooted in anecdotal and empirical herbalism rather than controlled scientific studies. Modern research into pennyroyal's efficacy for PMS is virtually nonexistent, and no clinical trials have substantiated its benefit for PMS Type P symptoms.

It is important to note that pennyroyal, especially its essential oil, is highly toxic and can cause severe liver and kidney damage, convulsions, and even death if ingested in significant amounts. Because of this, it is not recommended for use, and its historical application does not equate to safety or efficacy. In summary, while pennyroyal is traditionally associated with menstrual support, there is minimal evidence to scientifically justify its use, and safety concerns are significant.