Pennyroyal oil is an aromatic extract of several mint plants, particularly Mentha pulegium and M. canadensis and is used as an insect repellent, antiseptic, fragrance, flavoring, as an emmenagogue, carminative, stimulant, antispasmodic and for bowel disorders, skin eruptions and pneumonia.
Pennyroyal oil is extremely toxic to the liver of many animals, including humans. Symptoms of toxicity result within hours of application, beginning with listlessness, vomiting, diarrhea, and bleeding from the nose, mouth, and intestines. Exposure may possibly culminate with convulsions. Depending upon the amount of exposure, treatment may be futile, and death may ensue within one to two days.
Common symptoms include
Listlessness
Vomiting
Diarrhea
Coughing up blood
Difficulty breathing
Bloody nose
Lethargy
Coma
Seizures
Death