The 'magic' in magic mushrooms wasn't always a controlled substance.
Thousands of years ago – before substances were something laws sought to control – the psychedelic compound psilocybin was consumed by ancient cultures. Even as recently as decades ago, it was marketed in the US as a medicine, before the thinking around psilocybin changed.
Now, that thinking could be about to change again.
In a new paper, a team of researchers from Johns Hopkins University has evaluated the 'abuse potential' of medically administered psilocybin, and made the case for why the drug – if it passes a new round of clinical trials – should be reclassified as a Schedule IV drug in the US.
Other Schedule IV substances include things like Xanax, Valium, and Ambien – drugs with a "low potential for abuse and low risk of dependence", per the DEA's definition.
By contrast, Schedule I drugs – such as heroin, LSD, and MDMA – are considered to have "no currently accepted medical use and a high potential for abuse".
So if the called-for reclassification does indeed take place, psilocybin would go from being treated like an outlawed narcotic to – basically – a prescription sleeping pill.
"We want to initiate the conversation now as to how to classify psilocybin to facilitate its path to the clinic and minimise logistical hurdles in the future," says psychiatrist Matthew W. Johnson from the Johns Hopkins University School of Medicine.
"We expect these final clearance trials to take place in the next five years or so."
Part of the rationale behind the classification of Schedule IV drugs is that they're not recognised as having any medical potential, but a body of recent research has suggested that psilocybin can offer therapeutic benefits in things like alleviating depression and anxiety, especially when paired with therapy.
Of course, to reclassify the magic mushroom compound as a Schedule I substance, the FDA would also need to be convinced that psilocybin's abuse potential was low enough that it wouldn't create severe psychological and/or physical dependence in those who might take it as a medicine.
To that end, Johnson and his team reviewed the history of animal and human studies on the psychedelic, and explain in their paper that the drug is non-addictive, with "no clear evidence of physical dependence and withdrawal in preclinical or clinical studies, or among those who chronically used illicit products".
Further, its overdose potential is considered low, with doses that might pose a risk of acute poisoning death being about 1,000 times higher than what clinical doses might be.
"We should be clear that psilocybin is not without risks of harm, which are greater in recreational than medical settings," Johnson says.
"But relatively speaking, looking at other drugs both legal and illegal, it comes off as being the least harmful in different surveys and across different countries."
It's worth bearing in mind, if psilocybin does get reclassified by the FDA in the near future, it would be with a synthetic, mass-produced version of the drug in mind.
In other words, don't expect health authorities to give the green light to ingesting potentially dangerous toadstools that contain unknown dosages of the compound (let alone other chemicals beyond psilocybin).
"We believe that the conditions should be tightly controlled and that when taken for a clinical reason, it should be administered in a health care setting, monitored by a person trained for that situation," says Johnson.
There's no guarantee the researchers' argument will be listened to any time soon, and even if it is, there could be considerable red tape before psilocybin gets released in a new, regulated medical product.
But if it is, it might not just unlock therapeutic benefits for patients – but also resume a state of progress in our scientific understanding of this 'magic' chemical, which got hamstrung by legal restrictions in the 1970s.
"In the 1960s, they were on the cutting edge of neuroscience research and understanding how the brain worked. But then it got out of the lab," Johnson told The New York Times.
The findings are reported in Neuropharmacology.