The Truth About The Acid-Dipped Cigarette In Once Upon A Time In Hollywood

The new Quentin Tarantino movie Once Upon A Time In Hollywood takes place in 1969, a time when everything was groovy and drugs cost 50 cents. In one pivotal scene, Cliff Booth (played by Brad Pitt) gives Rick Dalton (played by Leonardo DiCaprio) a cigarette dipped in acid that he bought off of a hippie. Booth makes a big deal about putting it in Dalton's cigarette case and warns him not to smoke it.

This special cigarette becomes like a Chekov's gun throughout the rest of the movie. When Booth finally smokes it, he's already very intoxicated, and hallucinates. While he's tripping, some other very important things happen that we won't give away here. Whether you plan to see the movie or not, but you might be wondering: what exactly happens when a person smokes acid?

For a quick refresher, "acid" is the nickname for a psychedelic drug called lysergic acid diethylamide, or "LSD." When taken, LSD can cause profound hallucinations and sensory enhancements, according to the Drug Policy Alliance. LSD affects people in different ways (and it can change depending on someone's mood), but most people report visual sensations, unusual thoughts, and an overall excited mood. Time may feel like it slows down, and people tend to get in their feelings while on LSD.

In the '60s and '70s, around when Once Upon A Time In Hollywood takes place, lots of artists and musicians used LSD to enhance their creativity. Nowadays, there's promising research suggesting that LSD could have a therapeutic effect and be used to treat addiction, depression, and anxiety in the future, although LSD is still considered a Schedule I drug (which the Drug Enforcement Agency defines as having "no currently accepted medical use and a high potential for abuse"). Many people take regular micro-doses of LSD to improve their mood and cognitive functioning. Ironically, some people report that LSD can help people quit smoking tobacco.

Getting back to Booth's unconventional acid experience, LSD is typically consumed in small doses via a blotting paper or liquid dropper. It's pretty uncommon for people to smoke LSD, although smoking cigarettes dipped in other substances, aka "smoking wet," is a thing that some do to get high. For example, some people smoke cigarettes and joints that have been laced with phencyclidine (PCP) both intentionally or accidentally. This is highly dangerous and can lead to severe side effects including respiratory failure. Some Redditors theorize whether or not smoking LSD would actually produce the same psychedelic effects as taking it through the traditional routes.

This is complicated, according to Michael Chary, MD, PhD, an emergency medicine physician and fellow in medical toxicology at Harvard Medical Toxicology Program at Boston Children's Hospital. Technically, there hasn't been any research about the different effects of LSD when taken at different temperatures. Anecdotal reports suggest that smoking LSD has no effect at all. We do know that heat "promotes the inactivation of LSD," he explains. That means, the hotter the substance is, the harder time it has binding to serotonin receptors, and the less stable it is. "So, at hotter temperatures, LSD has less of a biological effect," he says. Sorry to be a buzzkill, Tarantino.

Obviously, Once Upon A Time In Hollywood is a fictional movie that takes some liberties with revisionist history. It could be possible that this character ingested some LSD on his lips when smoking the cigarette. Or, the cigarette could've been laced with DMT instead of LSD, a substance that mimics LSD and produces similar psychotropic effects. ("[DMT] hallucinations are more angry and violent than psychedelic colors," Dr. Chary adds.) The bottom line: Although this acid plot line is somewhat far-fetched, that doesn't mean that smoking LSD is safe — or a good idea.