Mentha pulegium is toxic to cats, dogs and horses. The reported severity is mild. Also known as Pennyroyal.
If your animal ate this plant, call your veterinarian, the ASPCA Animal Poison Control on (888) 426-4435 or the Pet Poison Helpline on (855) 764-7661. Fees may apply.
Vomiting Diarrhea
The color of each symptom follows the severity scale above.
Mentha pulegium, commonly (European) pennyroyal, or pennyrile, also called mosquito plant and pudding grass, is a species of flowering plant in the mint family, Lamiaceae, native to Europe, North Africa, and the Middle East. Crushed pennyroyal leaves emit a very strong fragrance similar to spearmint. Pennyroyal is a traditional folk remedy, emmenagogue, abortifacient, and culinary herb, but is toxic to the liver and has caused some deaths. European pennyroyal is related to an American species, Hedeoma pulegioides. Though they differ in genera, they share similar chemical properties.
Pennyroyal is toxic to humans and has differing effects dependent on the volume and concentration ingested. The most concentrated and toxic form of the pennyroyal plant is pennyroyal oil. The oil contains pulegone (a cyclohexanone), the molecule found in the highest concentration (80-92%) in the pennyroyal plant. Pulegone causes a variety of ailments in those who ingest it and is what causes the plant to have its peppermint flavor. Symptoms that may persist after ingesting a small dose (<10 mL) of pennyroyal oil are nausea, vomiting, abdominal pain and dizziness. Larger volumes may result in multiorgan failure that could lead to death. There are no current toxicokinetics studies performed on humans for the effects of pulegone, but there are some studies performed on other mammals. When pulegone is ingested, it is broken down by the liver and reacts to form multiple toxic metabolites that can wreak havoc in the body. Some identified metabolites are menthofuran, piperitenone, piperitone, and menthone. As little as 10 mL of pennyroyal oil ingestion was associated with moderate to severe hepatic toxicity.
Also recorded as European pennyroyal and penny-royal.
More from the Lamiaceae family:
Countries with the most wild observations, from GBIF data.