The psychedelics (or Hallucinogens) are a class of drugs that have a profound cultural mythos. They are often associated with social rebellion of the 1960’s and 70’s, and, conversely, with “spiritual” personalities and religious figures across dozens of cultures. Most people have either an automatically positive or negative view of these types of drugs. In this article, we want to briefly explain what they are and the state of research on psychedelics as potential treatments for mental health conditions.

Different Types

Psychedelic drugs are any drugs that induce hallucinations, delusions, or “mystical” experiences. There are many types of psychedelics, both natural (plants) and synthetic, with many more “lab” created drugs or “research chemicals.” In short there are, essentially, three classes of psychedelic drugs: Serotonergic, Glutamatergic, and cholinergic; however most use glutamate and Serotonin.

Serotonergic (5HT2a): LSD, Mescaline, Psilocybin (Mushrooms), MDMA (strong affinity for dopamine as well), and NBOME.

Glutamate drugs: PCP, Ketamine, MK801, Ibogaine

Cholinergic drugs: Scopolamine, Atropine

Brief History/Uses

Anthropologists have pretty detailed records about how many of the plant-based psychedelics were used across history. Some records show that mescaline and psilocybin (mushrooms) have been used in rituals for the past 5000 years, and the lab created drugs like LSD, MDMA, PCP, and Ketamine have only been around for approximately 70 years or so. Both LSD and MDMDA were created for other purposes (e.g., LSD for creating a new drug to make it easier to breath and increase blood flow) and then were misused later, typically on accident discovering their intoxicating capacity. A new (since 2003) category of lab created drugs called NBOME have, reportedly, worse negative side effects. Previously there was a drug Bromo-Fly, but now newer versions/altered versions are being created every year to keep up with consumer demand.

Research on Uses/Abuses

In animal studies, all of these drugs activate the dopamine system, or the “addictive” or “reward” pathway, which means they all possess addictive potential; HOWEVER, LSD and MDMA apparently have very low addictive potential in animal models compared to the glutamate built drugs. This means that people are able to get high with these drugs, but are at very low risk of “getting hooked.”

The good: LSD has been used by scientists to develop complex models of motor and mood problems, which helps with researching known disorders. Research consistently shows that drugs like psilocybin and LSD decrease functional connectivity in parts of the emotional and intellectual breaking system. This might be why they could help fight anxiety, PTSD, and other disorders. Another great finding from the literature is that low doses of LSD actually promote substantive changes in the personality trait of openness to experience, which is correlated with intelligence and creativity. The problem with drugs like ketamine for depression treatment and other psychedelics is we don’t have many long-term (i.e., over 6 month) studies and we’re not quite sure about dosing yet. It for sure works to relieve the affective, but less so the motivational/behavioral, component of depression at the neurological level, but does increase receptor connectivity, much like typical antidepressants.

The bad: It seems like LSD mixed with alcohol generally produces more negative effects mentally or during hallucinations. The other problem, and the research shows this consistently, using hallucinogens is that using them too often or intensely activates brain networks in essentially the same way as what we see in people with schizophrenia. As one study stated “regular use of psychedelic drugs could potentially lead to structural changes in brain areas supporting attentional processes, self-referential thought, and internal mentation.” A series of studies shows that, generally speaking, addictive potential is low, acute toxicity is in the moderate range, and chronic toxicity (i.e., damage to brain cells) is low to moderate. There’s also a “ceiling” to how “mystical” or transcendent you can feel/become when intoxicated on drugs like LSD, so there’s a misconception that people can just “trip” as much as they want.

At the end of the day, very mixed bag. We need much more research. Much of the stigma is unnecessary. The realistic consequences are minimal but still concerning.


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