A Storm of Chemistry
Moon tea offers the women of the Seven Kingdoms and beyond The Wall some control* over their lives – a rarity in a series. This herbal tea is a birth control method, implied – or explicitly stated – to be an abortifacient. In George R.R. Martin’s The Storm of Swords, a recipe for moon tea is given by Lady Lysa as “…tansy and mint and wormwood, a spoon of honey and a drop of pennyroyal.”
Moon tea is fiction, but three of its ingredients have long histories in birth control – tansy, wormwood, and pennyroyal plants. While the use of herbal abortifacients goes back far beyond a millennium, their effectiveness and safety is as inconsistent as the weather of Westeros. ASOIAF aficionado Butterfly wrote in 2013 “…moon tea is ~fantasy~, but don’t try it at home.” As Butterfly notes, our three historical plants are toxic. Why are these three plants toxic? It comes down to the chemicals pugelone and thujone. En route to these compounds are moon tea’s honey and mint.
Asoiaf.westor.org member Eden-Mackenzie pointed out, “[m]int and honey can be eliminated as the dangerous ingredients, and are likely included to help with taste and/or smell.” Butterfly’s moon tea post says honey and mint are safe. I would agree with safety assessment for honey and one of the two mints in Martin’s moon tea recipe. This fictional tea contains two members of the Menta genus – Mentha spicata and Mentha pulegium. By tradition, only Mentha spicata – commonly known as spearmint – gets the official nickname ‘mint‘. Mentha pulegium** is better known by its common name of pennyroyal.
Mentha genus members share many common properties and produce a lot of the same chemicals. Pennyroyal, along spearmint and peppermint, all produce R-(+)-pulegone, a chemical known simply as ‘pulegone’.
…patients may present within 2 hours of ingestion with nausea, vomiting, abdominal pain, burning of the throat, and dizziness before the delayed development of liver dysfunction. Significant pennyroyal oil ingestions can lead to fulminant hepatic failure, acute renal failure, disseminated intravascular coagulation, metabolic acidosis, gastrointestinal bleeding, pulmonary congestion, altered mental status, seizures, and death.
Pennyroyal oil, however, is highly toxic, and even small does (one tablespoon, 15 mL) can cause syncope, seizures, coma, cardiopulmonary collapse, acute liver injury, renal insufficiency and multiorgan failure.[emphasis added]
You can see why Martin’s recipe calls for only a drop of pennyroyal oil. Pennyroyal tea and leaf extracts, with their minty scent, has been used historically to flavor foods and beverages “…without serious side effects,” according to the NIDDK. It boils down to a higher dose of pulegone being required to see the “serious side effects” mentioned above. What about the abortive effect? Pregnancy termination “…may occur with marked maternal toxicity or death,” according to the NIH’s Toxicology Data Network. At the levels of pugelone that may end a pregnancy, come multi-organ and multi-system damage. The history of pennyroyal as an abortifacient is marked with serious maternal injury and death, with poor efficacy as an abortifacient, as detailed Kaye Wierzbicki’s ‘A Cup of Pennyroyal Tea‘ at The Toast. While a drop of pennyroyal might be safer, lower risk likely means no abortive effect.
Joining pennyroyal in this awful realm of dangerous, unpredictable herbal abortifacients are tansy and wormwood. Both tansy and wormwood are in Asteraceae plant family, diverging at the genus level. These two plants – Tanacetum vulgare L. (tansy) and Artemisia absinthium L. (wormwood) – share a common feature. Both produce alpha-thujone and beta-thujone, two isomers collectively called ‘thujone’.
Thujone, like pugelone, is classified a monoterpene. It smells like menthol (minty) and is a colorless oily-like liquid. Thujone is often classified as a neurotoxin based on its dose-dependent action on the central nervous system, with the most noted effect being epileptiform convulsions. Like pennyroyal, a cup of tansy or wormwood tea probably doesn’t contain enough thujone to bring about “serious side effects”. Tansy and wormwood oils would contain significantly more thujone and acute oil poisonings could result in the following:
…vomiting, gastroenteritis, flushing, cramps, loss of consciousness, rapid breathing, cardiac arrhythmia, enteric bleeding and hepatitis. Death occurs from circulatory or respiratory arrest and degenerative organ changes…
It doesn’t seem as if Martin’s moon tea recipe calls for the oils of tansy or wormwood. There’s no talk of drops, just herb names. This implies the use of leaves, either dried or fresh. In the real world, a cup of moon tea may^ not be enough to terminate a pregnancy, with the accompanying damage to maternal health. Like real herbal concoctions women have turned to throughout history, a few cups a day for a week would likely be consumed in pursuit of pregnancy termination. Such chronic, rather than acute, exposure in no way guarantees termination or maternal safety. If this tea worked in the Seven Kingdoms as it would in real life, the women of ASOIAF would face with the same poor birth control^^ options real women have faced throughout history and into the modern day. Good thing moon tea exists in fantasy world.
*This isn’t the case for Lady Lysa, but no spoilers here.
**This is European pennyroyal. American false pennyroyal, Hedeoma pulegioides L., also produces pulegone and its essential oil is ~30% pulegone.
^Dosage is key and this person’s size can determine the significance of a toxins impact.
^^Even in the fantasy world of ASOFAI, the choice to use moon tea can have terrifying consequences, but no spoilers here.
The featured image was created with clipart in PowerPoint.