Everything You Need to Know About Using Ketamine

11/13/20: This article has been updated throughout to reflect recent developments. 

By the spring of 2018, I’d tried most of the more common psychedelics, but ketamine seemed like a wild card. The stories people told me about it were all over the place—including a man who fell into a K-hole where he believed he was the carpet and couldn’t get up and a woman who called it the “ultimate spiritually transcendent experience.” I didn’t want to risk the former in pursuit of the latter.

That held true until some friends were snorting K in their apartment, and curiosity got the best of me. I told my friend to give me what she deemed a microdose (though I’m unsure of the actual dosage), then cut that in half just to be prudent. A few minutes in, all my emotions intensified. The dog’s bark made me jump. But once we started talking, it was like my ego’s defenses eroded and I could see myself from the outside. I analyzed my life as if I were in therapy, suddenly seeing the perspectives of people I was mad at. And I really wanted to cuddle. 

My friends told me they only felt ketamine for a few minutes — it usually lasts around an hour or two — but I stayed in that state all night. Unfortunately, what they’d told me about ketamine lacking a hangover didn’t hold up, either. I was foggy-headed and exhausted the next day.

Ketamine has traditionally been used as an anesthetic for medical procedures, first in veterinary clinics and then in people after the FDA approved it for human use in 1970. Shortly after that, it began taking off among hippies and then in 80s and 90s nightclubs, according to Steven Levine, a New Jersey–based psychiatrist and founder of Actify Neurotherapies, a treatment center with locations in several cities. Still, it’s more popular as a recreational drug in the UK and southeast Asia than it is in the U.S. 

Over the past decade or so, legal ketamine clinics have popped up to treat depression, OCD, and other mental health conditions. It sometimes has transformative effects for people who haven’t responded to conventional psychiatric medications, said Prakash Masand, a psychiatrist and founder of the Centers of Psychiatric Excellence, which specializes in Ketamine IV therapy for psychiatric conditions that haven’t been alleviated by other methods. “It has literally saved lives for people who were ready to give up all hope,” Masand said.

Because experiences with ketamine vary so drastically, it’s hard to know what you’ll feel on it. That said, here’s what you should know if you’re thinking of trying it.

What does it feel like to take ketamine?

Aside from being a sedative, Ketamine has dissociative properties, which means it can make you feel disconnected from your body and the world. “This may be accompanied by vivid dream-like feelings and out-of-body experiences,” Masand said.

At low doses, this can be a pleasant experience, making someone feel “at one with the universe,” said James Giordano, professor of neurology and biochemistry at Georgetown University Medical Center. Or, it might give them a more objective perspective on their lives, as it did with me.

This is why ketamine can be helpful for PTSD patients, Levine said—they can work through their trauma without reliving all the emotions associated with it. Those with depression may find it helps them feel “less isolated and less alone,” he said.

But at higher doses, people can experience derealization, or detachment from reality, which can lead you to make dangerous decisions. Some people fall into the aforementioned K-holes, where they’re temporarily immobile. “It is termed a ‘K-hole’ because a person is typically unable to process any external information and may appear to be immobile and not responding to verbal stimuli,” Masand said. “It may be accompanied by hallucinations and psychosis. There have been reports of individuals taking hours to come out of a K-hole.”

Other not entirely pleasant effects of ketamine can include anxiety, dizziness, or loss of balance. Patients often don’t enjoy the experience, and make comments like “time is going slowly” or “I feel a bit sunken in my chair,” Masand said. 

Ketamine might also affect sensory perception. For some people, colors get brighter and more intense, Levine said. At higher doses, many have full-on hallucinations. Others find that their hearing becomes more acute, which could explain why my friend’s dog freaked me out so much. “When we use it clinically, if somebody is in a room and there are whispered voices in another room or the other side of the building, you can clearly hear them,” Levine explained.

How long does a ketamine trip last?

Ketamine’s effects typically last for just about an hour, but they can continue for as long as a day, depending on the dose and method of ingestion, Masand said. Some people just sleep off lower doses of ketamine, but others may continue experiencing a sense of derealization the day after taking it, especially at high doses. Ketamine hangovers can also include “dizziness, incoordination, [and] impaired attention and memory,” according to Masand.

How do people use ketamine?

Recreationally, ketamine is usually snorted in powder form and occasionally taken as a pill, while in clinical settings, it’s often administered via IV or injections. Some clinics have therapists in the room supervising and talking to patients, while others leave you to yourself, often providing blindfolds or noise-blocking headphones to help you focus.

The main difference between different methods of ketamine administration is in the timing of the trip, said David Manjoubi, anesthesiologist and founder of Ketamine Healing Clinic of Los Angeles. Shots will come on more quickly and end more quickly than IVs, snorting will take longer than both, and oral administration takes the slowest to set in. 

Another, newer way of taking ketamine is through a nasal spray that can be prescribed to use at home as a treatment for depression or other mental health issues. This spray is made of a type of ketamine called esketamine, which is different in molecular structure, but has the same effects as the ketamine you typically hear about. As Mahjoubi explained, “Esketamine is just another form of ketamine.”

Unsurprisingly, people have appropriated esketamine spray as a party drug, with some ravers preferring the smaller, more controllable doses. “Some people call it a princess high,” said Giordano. “It’s light and wafty, not necessarily as profound, and the incidence of experiencing the K-hole phenomenon is less.” 

In another new model of ketamine therapy that’s gained popularity in the age of social distancing, some clinics will prescribe ketamine tablets for patients to take at home while they video chat with a clinician. 

So, wait, is ketamine legal?

Ketamine is a Schedule III drug in the U.S.—i.e., one with “a moderate to low potential for physical and psychological dependence.” It’s legal in medical settings, since it’s a commonly used anesthetic, so ketamine clinics that offer IV infusions or injections are doing everything above-board, as are patients who take prescribed esketamine spray. 

However, it’s still illegal to possess or sell ketamine outside of medical settings. Possession of small amounts of ketamine is typically a misdemeanor (resulting in a fine and up to a year in county jail), but manufacturing it, but selling or manufacturing schedule III drugs illegally could lead to as much as a $2.5 million fine or 15 years in prison.  

What are the risks of taking ketamine?

While ketamine is widely deemed safe in medical settings, this may not be the case when you use it recreationally. “If they take big doses on a frequent basis, it can permanently damage people’s bladders and hurt people’s brains,”  Levine said.

Ketamine is difficult to dose—particularly in powder form—and when people overdose, they may experience potentially fatal side effects, including central nervous system inhibition that can lead to cardiac arrest. Users also might get high blood pressure, which puts them at risk for heart attack, stroke, heart failure, aneurysm, renal failure, vision loss, and dementia.

Another difference between recreational and medical use of ketamine is that, in medical settings, it’s administered intravenously so that it comes up gradually. When it’s snorted or taken by mouth recreationally, it may hit a person all at once. The typical recreational forms of ingestion also don’t lead as much ketamine to get absorbed as an IV, Masand said: “Individuals compensate by taking larger amounts to get the highs.” 

After overusing ketamine for an extended period of time, some experience ketamine cystitis—damage to the bladder that can lead to pain and frequent urination. If a person really overdoes it, they could experience psychosis that resembles schizophrenia, even after they stop using ketamine.

Does ketamine show up on a drug test?

There are sophisticated urine and blood tests that can detect ketamine, but a standard urine drug test probably won’t pick it up, Masand said. 

What happens if you mix ketamine with other substances?

“Like all anesthetics, ketamine is not a good mixer,” said Masand. 

Mixing ketamine with alcohol can compound the dissociation and impaired judgment inherent in both substances, while weed plus ketamine can lead to anxiety, especially if weed tends to make you anxious in the first place. “The last thing you want is to mix an anxiety episode with a dissociative episode—that’ll freak [you] out,” Giordano said.

Some users say that mixing ketamine with MDMA, aka kitty flipping, can provide the social effects of MDMA combined with the introspective effects of ketamine. “[People who kitty flip may be] feeling very affectionate and demonstrative, and they’re also very reflective about the experience,” said Giordano. He said that those who do this—or any ketamine-psychedelic combination—should take low doses, because the effects of both substances compound each other. 

Some people are selling a form of street ketamine mixed with cocaine called “Calvin Klein,” a combination Giordano specifically cautioned against. “There have been a couple of case reports when people have shown up in an emergency room when they’re highly dissociated and on a coke high, so they completely act out or they become very agitated,” he said.

Can ketamine be cut with anything?

As with any substance, getting ketamine on the street carries the risk that it’ll be cut with other substances. Powder ketamine can be cut with really any powdery substance, sometimes including chalk, baking soda, coffee creamer, and gypsum dust (a material used in building construction), said Giordano. Sometimes, what’s marketed as ketamine is actually a substance called methoxetamine, or MXE, an experimental drug used for scientific research, said Giordano. Like ketamine, MXE affects the brain’s NMDA receptors, though some say it’s a lighter high, not unlike esketamine.

There’s also a chance that ketamine obtained outside medical clinics could be laced with other drugs—there have been reports in Australia of ketamine laced with opioids.

While at-home drug testing kits—which usually work by mixing your drugs with different substances and turning them different colors if something unusual is detected—may detect the most common substances mixed with ketamine, Mahjoubi doubted that they could pick up all possible adulterants. 

How should ketamine be dosed?

Self-treatment is not generally recommended: Since ketamine’s effects are very dose-dependent, people should  be careful about how much they take. If people do choose to self-dose, Giordano cautioned against exceeding a microdose, which would be around .02 mg under the tongue, or 0.2 mg orally, and to stay under 0.7 mg/kg of their body weight under the tongue and 1.4 mg/kg orally. 

Giordano also warned against taking ketamine more than once in one sitting. People may feel tempted, since the effects wear off fairly quickly, but the effects of multiple doses add up.

While ketamine continues to be valuable in surgeons’ and even psychiatrists’ offices, the consequences of using it recreationally are dicier. If a person chooses to venture into that territory, they should be as conservative as possible about how much they take and how often they take it.

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