The most awkward moment of my career came when I was working as a consultant at a natural-health store. A young woman came into the store looking disheveled and stressed and asked, “Do you guys have pennyroyal oil?”
Instantly assuming that she wanted it for the most common purpose — to induce abortion — I explained that I wouldn’t recommend it because it could be extremely dangerous.
“Do you have anything that does the same thing?” she asked, looking concerned.
“We do have parsley,” I said, “But you really should talk to an expert.”
“Okay,” she said, “Parsley gets rid of fleas?”
That intensely uncomfortable interaction proves that pennyroyal oil, like most herbal, is not used for one single purpose. It is in fact used to accomplish many different tasks, with varying degrees of risk. Here are some of the most common uses of pennyroyal oil.
Inducing Abortion
In the days of back-alley abortion, pennyroyal oil was a common go-to for women seeking to terminate unplanned pregnancies. It is, however, extremely toxic. There are dozens of documented cases of liver failure, kidney failure, and death in women using pennyroyal oil for this purpose. Although it can work to induce abortion, it does so only at doses high enough to kill the pregnant woman or cause irreversible organ damage.
Repelling Fleas
Applied to the fur of a pet, pennyroyal oil can help to repel fleas. It does not kill fleas, but instead makes the animal’s fur uninhabitable or unappealing to the pests. Pennyroyal oil can also be used in carpet treatment to repel fleas from home environments. It can pose a risk to pets who may accidentally ingest the product while grooming themselves, so it isn’t an ideal flea treatment.
Treating Head Lice
Pennyroyal oil may, in theory, help to kill or repel head lice, but there are other natural remedies available that are more likely to be safe and effective. The National Institutes of Health recommends avoiding all medicinal uses of pennyroyal oil, since it can cause liver damage even when absorbed through skin. Seek another treatment instead.
Treating Stomach Pain
Minute doses of pennyroyal oil have been used in the past to treat gas, indigestion, stomach pain and colon spasms. If you suffer from recurrent stomach pain, talk to your doctor about using enteric-coated peppermint oil, rather than pennyroyal oil, to ease your discomfort. It is far less toxic and there is far more evidence to back its efficacy.
Killing Germs
Like most essential oils, pennyroyal oil has antimicrobial properties and can help to disinfect surfaces. However, it is not worth the risk. Other, less toxic essential oils, such as tea tree oil and orange oil, are much safer and more effective for disinfecting skin and surfaces. It is not necessary or ideal to use pennyroyal oil for any purpose.
Medicinal herbs and their essential oils can be very safe and effective if used as recommended, under the guidance of a qualified health care provider. However, there are no beneficial uses of pennyroyal oil that are worth its very serious risks. Never use any medicinal product without first consulting a qualified professional. Visit the National Institutes of Health for more information about the most common medicinal uses of pennyroyal oil.
