The Truth About Psychedelic Drugs and Mental Illness

Photo: Paramount Pictures

Psychedelic drugs are confusing, and it’s easy to get very different views about them depending on whom you ask. On the one hand, enthusiasts — not to mention a small body of scientific research — have long claimed that, when taken responsibly and with the proper supervision, so-called classical psychedelics like LSD and psilocybin (the active ingredient in magic mushrooms) are a safe way to smooth the path toward tranquility and spiritual enlightenment. On the other hand, ever since the cultural spasms of the 1960s and a subsequent government crackdown on these substances, the archetype of the hallucinogen burnout has loomed large in the public imagination; that is, people who try LSD or ‘shrooms — sometimes even just once! — are forever ruined by flashbacks and other symptoms that eventually drive them to a state of full-blown psychosis.

For a while, researchers have believed these fears to be overblown. In fact, as Michael Pollan reported in a very interesting New Yorker article, those few researchers who have conducted recent experiments with psychedelics have come away rather impressed with their apparent potential to treat anxiety and depression in both patients with terminal illness and the general population (these are, to be sure, small, rather preliminary studies).

Now two new studies in the Journal of Psychopharmacology — one by Pål-Ørjan Johansen and Teri Suzanne Krebs, and the other by a team led by Peter Hendricks — have dealt a further blow to the idea that psychedelics are dangerous.

Both studies looked at the National Survey on Drug Use and Health, a big data set that includes information on a sample of Americans’ self-reported drug use and mental-health problems, among other things. Johansen and Krebs focused on “135,095 randomly selected United States adults, including 19,299 psychedelic users” — “psychedelics” here includes LSD, ‘shrooms, and mescaline, which is found in cactilike peyote — and sought out correlations between use of the drugs and various mental-health problems, as well as other outcomes.

Their key takeaway:

We failed to find any associations between lifetime use of psychedelics and past year serious psychological distress, receiving or needing mental health treatment, depression, anxiety, or suicidal thoughts or behavior in the past year. Rather, lifetime use of psychedelics was associated with decreased inpatient psychiatric treatment.

Hendricks’s study, which looked at a different slice of the same data set (“191,382 respondents, [of whom] 27,235 reported lifetime classic psychedelic use”), came to similar conclusions about the harmlessness of the substances, but focused more closely on suicide risk:

Consistent with hypotheses, lifetime classic psychedelic use was associated with a 19% reduced likelihood of past month psychological distress, a 14% reduced likelihood of past year suicidal thinking, a 29% reduced likelihood of past year suicidal planning, and a 36% reduced likelihood of past year suicide attempt. […] By contrast, lifetime illicit use of all other substances was by and large associated with an increased likelihood of psychological distress and suicidality at or above the trend level.

If classical psychedelics are in fact safe, where did all of the scary psychosis stories come from in the first place? The simple answer is media coverage, which, as everyone knows, sometimes over-blows certain fears, particularly when those fears are culturally resonant. The slightly more complicated answer has to do with a misunderstanding of what is causing what. “Psychedelics are psychologically intense, and many people will blame anything that happens for the rest of their lives on a psychedelic experience,” said Krebs in a Nature write-up of the new research by Zoe Cormier. The same goes for friends and family members: They might see a loved one fall victim to some mental illness and blame it on past psychedelic use, even if that psychedelic use didn’t in fact cause the affliction. (It’s hard to blame anyone for making this mistake, of course, given that even the top experts in the world don’t fully understand the causes of many mental illnesses.)

Both of these studies have a couple of limitations that are worth noting: One is that, as the researchers acknowledge, there are natural shortcomings to self-reported data, because people may sometimes report their habits or experiences inaccurately, intentionally or not (though, on the other hand, it’s often harder to get data sets of this size when you’re not relying on self-reported data, and bigger is better from a scientific perspective). The studies also left some drugs out — Nature noted that “[t]he authors did not include ketamine, PCP, MDMA, fly agaric mushrooms, DMT or other drugs that fall broadly into the category of hallucinogens,” because these drugs work differently on a biochemical and neurological level. (In that article, Nature quoted Johansen as acknowledging that PCP and ketamine, for example, can be dangerously addictive — LSD and ‘shrooms, on the other hand, are not considered to be addictive.)

But combined with the growing body of research that has failed to buttress the dangerous view of psychedelics that first took hold in the 1960s, these two studies would certainly seem to support a hastening of what Hendricks and his co-authors referred to as the “[g]radual return to research on classic psychedelics” that has occurred as the initial cultural panic over their use has waned a bit over the last 30 or so years. The problem is that despite the therapeutic promise these substances have shown — and, just as important, despite evidence that when used responsibly they aren’t linked to adverse effects — psilocybin and LSD remain Schedule I controlled substances in the U.S. (PDF), meaning it’s extremely hard to conduct the sorts of rigorous experiments that would be required to definitively pin down exactly what they can and can’t do. In fact, some researchers want to run these sorts of studies but don’t bother because of the many bureaucratic hurdles that hinder them.

That said, in various labs around the country this research is going on, hurdles notwithstanding, and in an email, Hendricks laid out what he saw as the way forward, now that the myth that classical hallucinogens are inherently dangerous has been mostly debunked. “I believe the most important next steps are evaluating the efficacy of classic psychedelics in treating suicidality as well as suicide pathogenesis [that is, what leads to suicidality], namely affective disturbance (i.e., mood disorders), substance misuse (i.e., addiction), impulsive-aggressive personality traits, traumatic histories, and neurocognitive dysfunction,” he said.

If classical psychedelics can help treat even a fraction of these conditions, it will have been worth the wait — and the decades of what appears to have been unnecessary fearmongering.