Monkshood (Wolfsbane) poisoning

Monkshood (Aconitum napellus) also called Wolfsbane, is pictured here growing in a hawthorn bush. This is a very poisonous plant. Aconitine, mesaconitine, hypaconitine and other alkaloids have potent cardiotoxins and neurotoxins found in all parts of the Aconitum species, especially in the tubers and roots.  The Latin name Aconite comes from the Greek ἀκόνιτον which means “without dust” and “without struggle”. It was used as a poison for arrow heads when hunting wolves (hence wolfsbane) and, as it is so fast acting, probably had then falling in the dust without a struggle

The neurotoxins, aconitine and mesaconitine can be absorbed through the skin and cause severe respiratory and cardiac problems. So do not pick or handle this plant without gloves, especially by the root.

Common signs of monkshood poisoning include tingling, tongue and mouth go numb, nausea with vomiting, breathing becomes harder and laboured, pulse and heartbeat become weak and irregular, skin is cold and clammy.

Patients with internal Aconitum poisoning will have cardiovascular (slows and stops the heart), neurological (pain, convulsions, paralysis), gastrointestinal symptoms (nausea and vomiting) and there are often other signs (for example, confusion and mania can occur if the alkaloids reach the brain). Multiple organ failure is likely. In autopsies, Aconitum alkaloid levels are found to be highest in the liver and kidneys, and lower in the heart and cerebrum, the latter having lower levels than the blood (Niitsu et al, 2012). The attached charts show the distribution of alkaloids in the organs at autopsy.

The estimated lethal dose is 2 mg of aconitine, 5 ml of aconite tincture and 1 g of the raw aconite plant (Chan, 2012; Qin et al., 2012). A 2mg dose of aconitine can cause death within 4 hours. Luckily cases of fatal monkshood poisoning are rare as it tastes foul and bitter and would quickly be spat out.

There is no known antidote.

As well as the already mentioned toxins aconitine, mesaconitine and hypaconitine, poisonous monkshood also contains at least a dozen other poisonous compounds, diterpenoid alkaloids, jesaconitine, lycoctonine, neopelline, neoline, benzoylaconines, and aconins. So not a baby to be messed with. Avoid picking a wild bouquet of it to take home!!

One of monkshood’s older common names was Venus’ Chariot so it may have been used in pagan flying ointments. So called “flying ointments” were allegedly used by witches (hence flying on broomsticks (wooden dildos)) where a balm or salve containing a poisonous herb was applied to the skin to control the dose. Sound evidence of this,as you can imagine, is missing. The purpose was to avail the shaman or witch of a dangerous herb’s intoxicants, getting high for visionary or mystical journeys, while avoiding some of the fatal effects. Don’t try this at home as just 2 milligrams of aconitine is lethal. Dangerous games!

Recently (Inquest Report June 2015) there was sad news in the media about the death of Nathan Greenway (7 Sept 2014), a gardener who died of multiple organ failure. He had allegedly brushed past a lot of monkshood (27 August) but had not handled any of it – to anyone’s knowledge. The coroner ruled that his death was due to unexplained causes.

In Nathan’s case, as death occurred some 10 days after developing symptoms, monkshood poisoning was ruled out as monkshood’s fatal effects are usually instantaneous. Also some of the symptoms were not those expected. For example it was reported that he was ‘drenched in sweat’ – was this the clamminess associated with Aconitum poisoning or a viral sweat?

Richard Greenway, Nathan’s father, who investigated and made the connection with monkshood poisoning, thought the plant was to blame. Asmat Mustajab, the histopathologist called for the pre-inquest hearing, also believed that aconitum “more likely than not” played a key role in Nathan’s death

Infuriatingly, the blood samples taken on his admission to hospital were destroyed – despite being labelled ‘To Be Retained’. As aconitines wreak their damage immediately but leave the body within 24 hours, it is theoretically possible that later analysis failed to detect aconitines – especially as they were not being looked for at the time as they thought he might have Ebola or another virus.

Modern intensive care can also keep patients alive for longer even with severe organ damage having been sustained.

I’m not in possession of the full facts and merely speculating from an uniformed position, but I would personally have thought that it was possible for Nathan to have died if he had handled the plants.  He may not have been observed handling them; if he had been working hard and sweating his skin pores would have been open; on a large estate ‘brushing against’ a colony of monkshood (rather than just a plant or two) could have had a cumulative effect; we are not told how long the leaves were in contact with his skin. But I wasn’t there, nor have I seen the inquest report, so in this case we must conclude that Nathan must have died for another reason. My thoughts are very much with the Nathan’s wife, father and family.

Regardless, do be aware of the plant and avoid handling it, especially by the roots. There is clinical evidence not just anecdotal that it can be absorbed by the skin (percutaneous poisoning). One of our @NapiersHerbs Twitter followers reported the following experience: “@RavenPulsar: Once I forgot to wear gloves & picked up a very young plant by the roots – hands went numb… washed hands & was ok thankfully (!)”


Chan, T.Y. (2012). Aconitum alkaloid content and the high toxicity of aconite tincture. Forensic Sci. Int., 222, 1–3
Niitsu et al. (2012). Distribution of Aconitum alkaloids in autopsy cases of aconite poisoning. Forensic Sci Int. 10(227), (1-3):111-7. doi: 10.1016/j.forsciint.2012.10.021.

Qin, Y., Wang, J., Zhao, Y., Shan, L., Li, B.C., Fang, F., Jin, C., & Xiao, X.H. (2012). Establishment of a bioassay for the toxicity evaluation and quality control of Aconitum herbs. J. Hazard. Mater., 199–200, 350–357

1 Comment

  1. Stephen Glover

    Obviously, this is the one to avoid…. I remember warning a vicar, who was tending his church garden, in Lancashire. As part of the floral display, Monkshood was at the fore, probably as it’s a fine looking plant….If you spot any, anywhere, make sure the local authorities know about it! Regards to All & Be Safe. Steve.

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