Mentha pulegium

Mentha pulegium

Synonyms

No documentation

Vernacular Name

True pennyroyal, Fleabane

Description

The common name of ‘Pennyroyal’ actually refers to two different plants:  Hedeoma pulegioides, known as American pennyroyal; and Mentha pulegium, known as European pennyroyal.  European pennyroyal is a perennial herb found in Europ and Asia, whereas American pennyroyal is an annual.  Both plants produce a light purple or blue flower.[1]  The information on the two plants is basically interchangeable.

Pennyroyal has a long history of use in foods as a flavoring as it has a taste and odor that is slightly similar to spearmint.  The essential oil of Pennyroyal is used in scenting soaps and as insect repellants.  The traditional uses that are not verified by science include its use as a remedy for spasms, flatulence, gall stones, gout, coughs and colds.[2]

While the use as an abortifacient is not conclusive, the misuse of Pennyroyal for this purpose has caused coma and death.[3]

M. pulegium is a perennial from the mint genus.  Growing to a height of 25cm, the stems of the plant are prostrate, and are square upon a cross-section, a common trait of the mint family.  The heavily branched stems are covered in a downy pubescence, so too, is the majority of the rest of the plant.  The leaves of M. pulegium are elliptical, pubscent, and have a scent similar to spearmint.  Very similar in many respects to H. pulegioides, M. pulegium can be identified by its smaller leaves, which are often, though not always, toothed.  The hermaphroditic flowers are small, and grow into whorl-like patterns to form their calyxes.  Blooming from August to October, each 1cm long flower is two-lipped, often bluish-lilac or lavender in color.  In contrast to H. pelugioides, the flower has four stamens, as opposed to two.

Origin / Habitat

M. pulegium originated in Europe and Asia and is thought to be naturalized in the United States via European colonists. It is often found growing near water, such as streams, pools and lakes.  M. pulegium flourishes in nutrient-rich, sandy, moist soil and sunny conditions.

Chemical Constituents

Pugelone, alpha-pinene, beta pinene, limonene, 3-octanone, p-cymene, 3-octylactate, 3-octanol, 1-octen-3-ol, 3-methylcyclohexanone, menthone, isomenthone, isopulegone, piperitone, lauric acid, myristic acid, palmitic acid among others.[2]

Plant Part Used

Herb

Medicinal Uses

General

Promoting menstrual flow
Insect repellant
Congestion
Coughs
Headache
Digestive aid

Most Frequently Reported Uses

Promoting menstrual flow
Insect repellant

Dosage

Dosage Range

2-5g dried herb steeped in hot water as a tea, 1-3 times per day.

Most Common Dosage

Tea:  5g per cup of hot water as directed per day.
Insecticide:  One drop of the essential oil in a carrier oil or lotion applied as directed.

Standardized to

There is no known standardization for M. pulegium.

Pharmacology

Pre-clinical

Although M. pulegium supplements are sold for use in coughs, congestion, and fevers, and to aid the stomach and digestion, these traditional uses of M. pulegium are not supported with scientific research.

The most reported and yet controversial use of M. pulegium is as an abortifacient. M. pulegium constituents (mainly pulegone) are reported to have emmenagogic properties, stimulating uterine contraction and promoting menstrual flow.[4] Although the essential oil has been used for centuries to induce abortion, there is no scientific proof to support this use. Therefore, the use of M. pulegium as an abortifacient cannot be substantiated by clinical evidence at this time.[5]

The use of M. pulegium as an antibacterial agent and insect repellent is supported by laboratory studies.[6] The essential oils, including pulegone, are the components that are responsible for the antimicrobial and insecticidal activity.[7]

Clinical

No documentation

Interaction and Depletions

Interaction with other Herbs

No documentation

Interaction with Drugs

Do not use M. pulegium supplements if taking prescription or non-prescription medications without the supervision of a trained medical professional.

Do not use M. pulegium supplements if taking medications that are potentially damaging to the liver, such as acetaminophen, statin medications, and certain antibiotics.

Precautions and Contraindications

Side effects

M. pulegium may cause allergic reactions such as contact dermatitis. Do not use if allergic to M. pulegium or the essential oils of M. pulegium.[10]

Do not use in individuals with liver or kidney problems.

M. pulegium oil ingestion has been associated with severe hepatotoxicity and death.[8] The primary constituent, R-(+)-pulegone, is metabolized via hepatic cytochrome P450 to toxic intermediates.

Death has been reported after consumption of half an ounce (15mL) of the oil.[9] If ingestion of M. pulegium is suspected there will be a characteristic strong, minty smell on the patient’s breath. Healthcare personnel can determine if M. pulegium ingestion is the cause of toxicity by using gas chromatography to test for the active metabolite menthofuran in urine, blood, or other tissues. Overdose management includes lavage, and/or administration of activated charcoal. Symptoms of M. pulegium toxicity may mimic that of acetaminophen.

Pregnancy

Based on historical use, M. pulegium should not be used in pregnancy due to the potential for abortifacient effects.[11]

Age limitation

No documentation

Adverse reaction

No documentation

Read More

  1) Essential Oil

  2) Native American Herbs

References

  1. Simon JE, Chadwick A and Craker L. Herbs: An Indexed Bibliography. The Scientific Literature on Selected Herbs, and Aromatic and Medicinal Plants of the Temperate Zone. Hamden CT: Archon Books; 1971-1980.
  2. Duke JA. Handbook of Medicinal Herbs. Florida: CRC Press; 1985.
  3. McGuffin M, et al. Botanical Safety Handbook. Boca Raton: CRC Press; 1997.
  4. Black DR. Pregnancy unaffected by pennyroyal usage. J Am Osteopath Assoc. May1985;85(5):282.
  5. Soares PM, Assreuy AM, Souza EP, et al. Inhibitory effects of the essential oil of Mentha pulegium on the isolated rat myometrium. Planta Med. Mar2005;71(3):214-218.
  6. Mahboubi M, Haghi G. Antimicrobial activity and chemical composition of Mentha pulegium L. essential oil. J Ethnopharmacol. 26Sep2008;119(2):325-327.
  7. Martins HM, Martins ML, Dias MI, et al. Evaluation of microbiological quality of medicinal plants used in natural infusions. Int J Food Microbiol. 15Aug2001;68(1-2):149-153.
  8. Carmichael PG. Pennyroyal metabolites in human poisoning. Ann Intern Med. 1 Feb1997;126(3):250-251.
  9. Bakerink JA, Gospe SM Jr, Dimand RJ, Eldridge MW. Multiple organ failure after ingestion of pennyroyal oil from herbal tea in two infants. Pediatrics. 1996;98(5):944-947.
  10. Pérez-Calderón R, Gonzalo-Garijo A, Bartolomé-Zavala B, et al. Occupational contact urticaria due to pennyroyal (Mentha pulegium). Contact Dermatitis. Oct2007;57(4):285-286.
  11. Anderson, Ilene B.; Sidney D. Nelson and Paul D. Blanc. Pennyroyal Metabolites in Human Poisoning. Annals of Internal Medicine. 1997; 126(3):250–251.

1.     Simon JE, Chadwick A and Craker L. Herbs: An Indexed Bibliography. The Scientific Literature on Selected Herbs, and Aromatic and Medicinal Plants of the Temperate Zone. Hamden CT: Archon Books; 1971-1980.

2.     Duke JA. Handbook of Medicinal Herbs. Florida: CRC Press; 1985.

3.     McGuffin M, et al. Botanical Safety Handbook. Boca Raton: CRC Press; 1997.

a.      

  1. Black DR. Pregnancy unaffected by pennyroyal usage. J Am Osteopath Assoc. May1985;85(5):282.
  2. Soares PM, Assreuy AM, Souza EP, et al. Inhibitory effects of the essential oil of Mentha pulegium on the isolated rat myometrium. Planta Med. Mar2005;71(3):214-218.
  3. Mahboubi M, Haghi G. Antimicrobial activity and chemical composition of Mentha pulegium L. essential oil. J Ethnopharmacol. 26Sep2008;119(2):325-327.

7.     Martins HM, Martins ML, Dias MI, et al. Evaluation of microbiological quality of medicinal plants used in natural infusions. Int J Food Microbiol. 15Aug2001;68(1-2):149-153.

  1. Carmichael PG. Pennyroyal metabolites in human poisoning. Ann Intern Med. 1 Feb1997;126(3):250-251.
  2. Bakerink JA, Gospe SM Jr, Dimand RJ, Eldridge MW. Multiple organ failure after ingestion of pennyroyal oil from herbal tea in two infants. Pediatrics. 1996;98(5):944-947.
  3. Pérez-Calderón R, Gonzalo-Garijo A, Bartolomé-Zavala B, et al. Occupational contact urticaria due to pennyroyal (Mentha pulegium). Contact Dermatitis. Oct2007;57(4):285-286.

11. Anderson, Ilene B.; Sidney D. Nelson and Paul D. Blanc. Pennyroyal Metabolites in Human Poisoning. Annals of Internal Medicine. 1997; 126(3):250–251.