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An Australian MD, and a mycologist, have been the first to publish a study on Wood-lover’s Paralysis, a rare toxidrome associated with ingesting species of ‘magic mushrooms.’
InSight+ spoke with the researchers, who say the medical community needs to know about WLP.
Wood-lover’s Paralysis (WLP) is an extremely rare, but potentially fatal, toxidrome causing unpredictable muscle weakness.
Dr Simon Beck, an MD in his final year of psychiatry training, and Mr Caine Barlow MSc, a mycologist and education officer for Ethnogenesis Australis, along with Dr Monica Barratt and Dr Liam Engel, have been the first to describe Wood-lover’s Paralysis in a study published in Toxicon.
According to the Victorian Coroner’s report, released this month, WLP was potentially associated with the death of Rachael Lee Dixon, who ingested magic mushrooms at a wellness retreat last year.
Coroner Audrey Jamieson declared the cause of Dixon’s death undetermined, but that it occurred in the context of symptoms suggestive of WLP. Dixon had experienced trouble walking, and breathing.
The coroner referenced the researchers’ work on WLP in her report.
“Dr Beck drew my attention to a toxidrome called ‘wood-lover paralysis’, which is associated with the consumption of certain lignicolous mushrooms containing psilocybin and is characterised by experience of transient weakness,” wrote Jamieson.
The coroner went on to quote Dr Beck directly.
‘‘Given the nature of the weakness described, seemingly having the ability to affect skeletal muscle broadly and at times quite severely, as well as the reports of subjective breathing difficulties, it seems reasonable to infer that respiratory depression and potentially respiratory arrest due to muscle weakness may be rare but possible consequences of Wood-lover’s Paralysis.”
What is Wood-lover’s Paralysis?
Dr Beck and Mr Barlow began their research into WLP around six years ago.
“I became interested after witnessing WLP through some harm reduction volunteer work and decided to study it in 2019 after hearing anecdotal reports. I realised there was nothing specific about WLP in the medical literature,” said Dr Beck.
Mr Barlow said that the research came about as citizen science.
“Dr Beck and I were both involved in harm reduction online, helping identify mushrooms. A question coming up regularly was, ‘What is Wood-lover’s Paralysis?’ or narratives like, ‘I fell to my living room floor and couldn’t move,’” he said.
“We designed a survey to systematically describe it, asking what mushrooms people were taking, the habitat and substrate the mushrooms were collected from, how people were consuming them, and to describe their experience of WLP.”
The research faced early hurdles when some clinicians expressed disbelief in WLP, and others felt the illegality of psilocybin mushrooms would pose barriers.
“The first step was to describe the symptoms. Our survey got a surprising number of responses,” said Dr Beck.
“We surveyed people who had experienced WLP, and people who had used psilocybin and not experienced WLP, to allow for comparison and to assess for any obvious individual or environmental factors.”
The survey included responses from 165 people who had experienced WLP. Many had experienced it more than once, but most had consumed the same species of mushrooms at other times without experiencing the toxidrome.
“Time to onset of weakness ranged from 15 minutes to 18 hours but occurred within four hours in 75% of cases. Distribution and extent of weakness was also highly variable, but ability to walk was impaired in 80% of cases,” said Dr Beck.
The effect of WLP on ability to function was rated at 7-10/10 in a third of cases.
“Concerningly, 1/4 experienced difficulties swallowing at some point, and 1/6 had subjective difficulties breathing.”
Currently, Dr Beck and Mr Caine are focusing on one case of respiratory arrest suspected to be caused by WLP in which, after spontaneous breathing returned following CPR, the person had another respiratory arrest in an ambulance on the way to the hospital, requiring intubation and mechanical ventilation.
Dr Beck says the case highlights the importance of awareness of the potential time course of WLP.
“If you’ve been struggling to breathe and when the ambulance arrives you feel OK, you should still go to hospital to be observed, to make sure it doesn’t come back. Because we know it can.”
WLP muscle weakness was sporadic, occurring in ‘waves’ of up to an hour. Weakness persisted into the following day in half the cases, resolving within three days without lasting consequences. Reported high-risk incidents included falls, and situations while driving, swimming, riding a bicycle, and crossing roads.
An ambulance was only called in three cases.
“This may reflect concerns about prosecution after using an illicit substance, or an awareness of WLP and a perception that it cannot lead to serious harm.”
What the medical community needs to know about WLP
Dr Beck says the medical community needs to know that WLP is a real, physical phenomenon, it is not psychosomatic and not caused by psilocybin itself.
“WLP is rare, and the most common “magic mushroom” variety [Psilocybe cubensis] does not cause WLP,” said Dr Beck.
“WLP is only associated with ingestion of the wood decomposing Psilocybe species which grow in cold climates in Australia – named Psilocybe subaeruginosa – and even then, this species only causes WLP rarely,” said Dr Beck.
“Psilocybin itself is generally considered quite physiologically safe, with an expected transient and generally clinically insignificant rise of blood pressure and heart rate. QT prolongation or other arrhythmia may be a very rare potential consequence. There is a very low risk of significant drug-drug interactions due to psilocybin’s pharmacological profile. Serotonin toxicity is not considered a risk due to its weak partial agonism of 5HT2a and lack of serotonin releasing properties,” said Dr Beck.
“Obviously, that is not to say they are risk free. Most serious adverse events associated with psilocybin mushroom use, however, result from psychological and behavioural disturbance.”
Dr Beck said that there is no data to draw on to determine how common WLP is.
“Anecdotally, it is considered quite rare,” he said.
In the 2022-2023 National Drug Strategy Household Survey, 1.8% of respondents had used psilocybin in the previous 12 months.
“If WLP was common, even with the still less common occurrence of severe symptoms, we would expect more people would be presenting for emergency treatment, which does not seem to be the case from discussions with those who provide toxin advice.”
“Harm reduction hinges on educating those who take magic mushrooms, and those who provide support if an adverse outcome arises.”
“Improving knowledge of WLP within the medical community, particularly paramedics, emergency physicians and clinical toxicologists, requires further focus.”
Dr Beck said that it is important to study psilocybin for its use in mental health.
“We desperately need more options for treating common mental health conditions like major depression, anxiety disorders, trauma disorders, OCD, addiction and eating disorders. Early clinical research findings using psilocybin for MDD and GAD are promising,” he said.
The researchers are looking at the next steps in learning more about the toxidrome.
“We need to discover the causative agent of WLP. This will require chemical analysis of specimens that cause WLP compared to specimens of the same species which do not.”
The Australian Psychedelic Society has published a harm reduction information leaflet addressing WLP.
Watch a video presentation of Dr Beck and Mr Barlow’s WLP findings, here.
Becca Whitehead is a freelance journalist and health writer. She lives in Naarm and is a regular contributor to the MJA’s InSight+.
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