There’s been a lot of buzz about pennyroyal on the interbutts. Even if you don’t fall in the demographic of people like to ever have to worry about pregnancy, you might know what large doses of pennyroyal does just through cultural osmosis.
Unfortunately, the lovely herb’s use is controversial for good reason.
Pennyroyal Magical Uses and Folklore
Pennyroyal is either feminine and ruled by the planet Venus, or else its masculine and ruled by Mars. While this is confusing, I feel like it illustrates the dualistic nature of this herb very well — it’s an objectively beautiful plant, with its lush, creeping growth and clusters of purple flowers invariably covered in bees and butterflies, but it’s also a deadly poison.
As an herb for travelers, a few leaves placed in each shoe was believed to offer protection and guard against tired feet.
Because of the herb’s use as an emmenagogue, it’s sometimes used as an ingredient in sachets and jars for blood magic and protection (especially for sex workers).
Interestingly, this herb is also used for peace. When carried or hung in a space, it helps keep tempers from flaring. (Be very cautious to avoid hanging it where pets or children might ingest it!) This might be an extension of its use as protection against the evil eye. If you think about it, it makes sense — it’s a soft, fuzzy, flowery herb with an unassuming appearance, but it hides a potent poison. Pennyroyal is pretty much the embodiment of an iron fist in a velvet glove.
Pennyroyal is also used to break hexes and curses.
The botanical name, Mentha pulegium, stems from its ability to repel fleas. This might also be the source of its protective powers — it chases fleas and negative or malevolent energies away.
In ancient Greece and Rome, wearing a crown of pennyroyal was believed to relieve headaches. The herb was also used to flavor savory foods.
Pennyroyal is still used in North African cuisine to this day. The US Food and Drug administration allows naturally-derived pulegone, a compound found in pennyroyal, as a flavoring agent.
Pennyroyal as Medicine
Pennyroyal is a mint. Members of the mint family contain a naturally-occurring compound called pulegone, which appears to be the primary source of this herb’s toxicity. Even when it isn’t acutely toxic, pulegone has been found to cause pre-cancerous changes in the organs of rodents. The thing is, while herbs like catnip and peppermint have much less pulegone, pennyroyal has a lot.
With that in mind, let’s talk about something called the “therapeutic window.” Put briefly, this is the range where you get the benefits of a medicine, without significant adverse effects. Some medications have a pretty broad therapeutic window. Some do not. Some therapeutic windows are so narrow, they’re not worth considering as treatment.
Pennyroyal falls squarely into that last category.
The thing is, pennyroyal does have some medicinal benefits. Traditionally, it was used as an ingredient in teas. It’s said to be good for flatulence and stomach cramps, like many other members of the mint family.
This is all in very low doses, however, and the beneficial effects of pennyroyal can be found in other, much safer herbs. Flatulence? Try a carminative like caraway seed. Indigestion? Regular peppermint will probably do you just fine.
Pennyroyal also has a reputation as an abortifacient and emmenagogue, meaning that it can trigger an abortion or bring on a period that’s been delayed. The dosage required to do this is pretty much at the far end of the therapeutic window, and the variability in strength of herbal medicine makes it impossible to figure out the difference between “safe and effective” and “deadly.”
Think of it this way — plants aren’t inert. They respond to their environment. If there’s heat stress and a lot of pests, they produce more of the volatile compounds that help them survive. If they’re in a relatively low-stress area, or pampered in a greenhouse, they’ll likely be less intense. This means that, if you’re trying to figure out your own dosage of pennyroyal, you’re pretty much flying blind. You have no way of knowing how much pulegone a given dosage of pennyroyal might contain.
That means that not only might you not actually trigger an abortion, you could end up destroying your liver, kidneys, and lungs instead. Worst case scenario, you will die and it will hurt the entire time. Just like everything else, there are much safer herbs that can help bring about a late period.
I have only one piece of advice when it comes to using pennyroyal medicinally: Don’t, unless you’re doing so under the guidance of a doctor. Unfortunately, we don’t yet have an antidote for pennyroyal poisoning.
While it’s still used in dishes like batata bel fliou, if you don’t have experience cooking with pennyroyal, it’s best to err on the side of caution and avoid putting it in brews, potions, or foods.
Oil of pennyroyal is the most toxic form of the plant, so you may wish to find an oil with comparable magical uses instead — especially for anointing.
Other than that, pennyroyal is fine to use in jars, sachets, and spells that don’t involve taking the herb internally. Since it’s been shown that it can cause pre-cancerous changes in the lung cells of rats, I’d probably avoid putting it in incense. (Members of the mint family tend to smell awful when burned, anyhow.)
If you’re a sex worker (or just someone who enjoys sex and wants to protect themselves), you might want to include it in a jar for attraction and sensuality as a sex-specific protection herb. Combine it with ingredients like rose petals, jasmine, and sugar, seal with the wax of a red candle, and keep it under your bed.
For protection, fill a jar with pennyroyal, cactus spines, garlic, and hawthorn. Keep it under your porch, or bury it near/under your front steps.
For peace, mix pennyroyal with lavender and thyme and put it in a jar. Seal it with the wax of a white candle, and keep it in a safe place near the heart of your home.
Pennyroyal isn’t immediately and intensely poisonous like some herbs can be, but the people most likely to look for it for medicinal purposes are at the most risk. If you’re experiencing menstrual irregularities or a late period, there are other treatments out there that are much safer for you.