- The essential oil of pennyroyal is considered toxic. Death has been reported after the consumption of small amounts. A characteristic noted in most cases of pennyroyal overdose is a strong minty smell on the patient's breath.
- A possible role for N-acetylcysteine (NAC) in the management of pennyroyal overdose has been suggested. However, this application has not been confirmed by animal or human studies.
- The essential oil of pennyroyal may act as an emmenagogue (menstrual flow stimulant) and induce abortion. However, it may do so at lethal or near-lethal doses, making this action unpredictable and dangerous. Future research to determine the safety and efficacy of the less toxic parts of the pennyroyal plant on the menstrual cycle is needed before a recommendation can be made.
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ingredients
American pennyroyal (Hedeoma pulegioides L.), European pennyroyal (Mentha pulegium L.)
Contents
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to . Selected references are listed below.
- Anderson IB, Nelson SD, Blanc PD. Pennyroyal metabolites in human poisoning. Ann Intern Med 1997;126(3):250-251.
- Anderson IB, Mullen WH, Meeker JE, et al. Pennyroyal toxicity: measurement of toxic metabolite levels in two cases and review of the literature. Ann Intern Med 4-15-1996;124(8):726-734.
View Abstract - Bakerink JA, Gospe SM Jr, Dimand RJ, et al. Multiple organ failure after ingestion of pennyroyal oil from herbal tea in two infants. Pediatrics 1996;98(5):944-947.
View Abstract - Black DR. Pregnancy unaffected by pennyroyal usage. J Am Osteopath Assoc 1985;85(5):282.
View Abstract - Buechel DW, Haverlah VC, Gardner ME. Pennyroyal oil ingestion: report of a case. J Am Osteopath Assoc 1983;82(10):793-794.
- Carmichael PG. Pennyroyal metabolites in human poisoning. Ann Intern Med 2-1-1997;126(3):250-251.
View Abstract - Ciganda C, Laborde A. Herbal infusions used for induced abortion. J Toxicol Clin Toxicol 2003;41(3):235-239.
View Abstract - Conway GA, Slocumb JC. Plants used as abortifacients and emmenagogues by Spanish New Mexicans. J Ethnopharmacol 1979;1(3):241-261.
View Abstract - Giorgi DF, Lobel D, Morasco R, et al. N-acetylcysteine for pennyroyal oil toxicity. Vet Human Toxicol 1994;36(4):358.
- Gordon WP, Huitric AC, Seth CL, et al. The metabolism of the abortifacient terpene, (R)-(+)-pulegone, to a proximate toxin, menthofuran. Drug Metab Dispos 1987;15(5):589-594.
View Abstract - Khojasteh-Bakht SC, Chen W, Koenigs LL, et al. Metabolism of (R)-(+)-pulegone and (R)-(+)-menthofuran by human liver cytochrome P-450s: evidence for formation of a furan epoxide. Drug Metab Dispos 1999;27(5):574-580.
View Abstract - Mack RB. "Boldly they rode ... into the mouth of hell." Pennyroyal oil toxicity. NC Med J 1997;58(6):456-457.
View Abstract - Martins HM, Martins ML, Dias MI, et al. Evaluation of microbiological quality of medicinal plants used in natural infusions. Int J Food Microbiol 8-15-2001;68(1-2):149-153.
View Abstract - Mazur LJ, De Ybarrondo L, Miller J, et al. Use of alternative and complementary therapies for pediatric asthma. Tex Med 2001;97(6):64-68.
View Abstract - Sullivan JB Jr, Rumack BH, Thomas H Jr, et al. Pennyroyal oil poisoning and hepatotoxicity. JAMA 12-28-1979;242(26):2873-2874.
View Abstract
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