Guide 4 of 5 · folklore with its feet on the ground
The shelf in the shadow. Read on while it turns.
The old books of witchcraft are full of plants that kill. Some of them are still sold, and some grow in British gardens. The Society keeps the folklore and drops the harm. So before you mix (Guides 2 and 5), here is what you must never mix, burn or brew.
Everything below comes from a named source in our library, and each one is listed under its rule. Where our library is silent, we say so, and we don't guess.
St John's wort can speed up how the body clears many medicines. That can make the contraceptive pill, heart medicines, HIV and cancer drugs and some blood thinners work less well. Taken with other antidepressants it can cause serotonin syndrome, which can be life-threatening. It can also make skin sensitive to sunlight.
If you take any medicine at all, ask a pharmacist before you go near it.
Source: "Hypericum perforatum", Wikipedia.
Comfrey contains pyrrolizidine alkaloids, which damage the liver. In 2001 the US Food and Drug Administration banned comfrey products made to be taken internally, and required a warning on those made for the skin. It is particularly discouraged in pregnancy, breastfeeding, babies, and people with liver, kidney or blood-vessel disease.
Source: "Symphytum" (comfrey), Wikipedia.
Datura is linked to witchcraft in many cultures, which is why people still ask for it. Every datura species is extremely poisonous, seeds and flowers most of all. Taken in, it can cause delirium, psychosis, heart rhythm problems and death, and its strength changes plant to plant, so there is no safe amount. Children are especially vulnerable. The Society does not sell it.
Source: "Datura", Wikipedia.
Foxglove grows wild across Britain. Its leaves, flowers and seeds are all poisonous and can be fatal if swallowed. Its heart chemicals have a very narrow margin: a tiny extra amount is the difference between nothing and a fatal dose. Leave it in the hedge.
Source: "Digitalis purpurea", Wikipedia.
Pennyroyal is on the list of herbs with a likely cause-and-effect link to harm, next to aconite, comfrey and germander. It appears in old recipes, but it is toxic to the liver and has caused deaths. It has no place in a modern blend, even for scent.
Sources: "Herbalism", Wikipedia; "Mentha pulegium", Wikipedia.
The medicines most often caught up in herb interactions are warfarin, insulin, aspirin and digoxin, because the gap between a working dose and a harmful one is small. The herbs most often involved include St John's wort and ginkgo. A pharmacist can check your mix in two minutes.
Source: "Drug interaction", Wikipedia.
Few studies exist on the safety of herbs in pregnancy. Some herbs were used in the past precisely to end pregnancies. If you are pregnant or trying, ask your midwife or doctor before any herb goes in a cup, a bath or a blend.
Sources: "Herbalism", Wikipedia; "Abortion", Wikipedia.
Burning sage, resin or herbs makes smoke, and smoke is not just scent. A fire short of air makes carbon monoxide and other toxic compounds, and smouldering makes more of them. Burn a little, in a heatproof dish, with a window open, and never leave it alone.
Source: "Smoke", Wikipedia.
Our library's sources name a few dangers we can pass on: onions and garlic can cause anaemia in dogs, and lilies can cause severe kidney damage in cats. For any other herb, the library is silent, so ask your vet before you burn, diffuse or leave herbs where animals can reach them.
Source: "Pet", Wikipedia.
Datura, foxglove and the nightshades turn up again and again in witchcraft lore because they were powerful, and because they were dangerous. The old herbalists also gave every herb a planet: in Real Alchemy, Robert Allen Bartlett lists pennyroyal among the herbs of Venus.
Keep the story, not the plant: read about them, draw them, light a candle for them, but don't mix them.
Sources: "Datura", Wikipedia; R. A. Bartlett, Real Alchemy: A Primer of Practical Alchemy.
The Society's five guides: 1 How to mix oils · 2 How to mix herbs · 3 Never mix these with your oils · 4 Never mix these herbs · 5 Herbs and oils together
This is folklore and general safety information from named sources. It is not medical advice. If you are pregnant, take medicines, have a health condition, or have children or animals at home, ask a pharmacist, doctor or vet before using herbs or essential oils. The Wand & The Crystal Ball Society is part of Peckham Crystals · Increatus, London.