Cannabis Induced Psychosis, an Interview with Dr. Amy Zimmerman

Updated March 31, 2026

Understanding Cannabis Induced Psychosis and Treatment

Cannabis induced psychosis (CIP) is becoming more common as cannabis use increases and products become more potent. While many people use marijuana without issue, it can sometimes trigger symptoms such as hallucinations, delusions, and disorganized thinking.

Writer Laura Eshelman, MSW sat down with CooperRiis Asheville’s integrative psychiatrist, Dr. Amy Zimmerman to explore how cannabis induced psychosis (CIP) affects mental health and recovery. They discuss what cannabis induced psychosis is, who is most at risk, how it can overlap with conditions like bipolar disorder or schizophrenia, and what thoughtful treatment can look like for those seeking help.

The summary below covers the key topics and answers a few common questions. Find the complete interview transcript at the end of the summary.

What is Cannabis Induced Psychosis (CIP)?

Cannabis induced psychosis (CIP) is described as a psychotic episode (hallucinations, delusions, or severe disorganization) that appears directly linked to cannabis use, often with abrupt onset and usually resolving after the drug leaves the system.

How Does CIP Differ from Other Psychosis?

Clinically, it can look very similar to other forms of psychosis, but it tends to come on rapidly in close temporal relationship to use, whereas primary psychotic disorders usually develop more gradually over time. For psychosis to be considered substance-induced, symptoms are expected to resolve once the substance is out of the body; if they persist, clinicians must consider an underlying primary psychotic disorder instead.

How Long Does Cannabis Induced Psychosis Last?

Different substances have different elimination times; that of cannabis is ~1 to 2 weeks. Cannabis psychosis can last anywhere from one day to two weeks, with many symptoms subsiding after 24 to 48 hours.

Cannabis Induced Psychosis Treatment

Clinicians may prescribe antipsychotic medication to be continued for at least one to three months after a severe episode, as long as they are tolerated.

The CIP Prognosis

If a person stays sober, tapers off antipsychotics, and remains well, that pattern supports a diagnosis of substance-induced psychosis. If symptoms return off medication, cannabis may have exposed an underlying condition such as schizophrenia or another psychotic disorder. Dr. Zimmerman highlights a common teaching: “Genetics load the gun, drugs pull the trigger,” emphasizing that cannabis can unmask latent psychosis in biologically predisposed individuals.

Individual Risk Factors for Cannabis Induced Psychosis

The strongest individual risk factor Dr. Zimmerman cites is a personal history of bipolar disorder or previous psychosis, with depression or general anxiety carrying much less added risk. Family history—especially a first-degree relative with schizophrenia or bipolar disorder—also meaningfully increases risk.

As for demographics, Dr. Zimmerman says she tends to see CIP more often in late teens and early 20s than in older groups. She notes that if someone has used heavily for 10–20 years without psychosis, it likely would have emerged earlier if cannabis were going to trigger it.

Substance-Related Risk Factors for CIP

Modern high-THC products (“you’re not smoking your grandpa’s weed”) and synthetic or concentrated forms (including dabs and delta-8) appear more likely to precipitate psychosis, and the doctor reports seeing delta-8 cause just as much psychosis as delta-9 in her practice.

CIP can occur on the very first exposure to cannabis, especially in vulnerable people or with potent products. More potent delivery methods as well (such as concentrated inhaled forms) seem to increase the chance of psychosis, whether smoked or otherwise inhaled.

CIP Treatment Approach at CooperRiis

The first line of treatment for CIP is antipsychotic medication, which Dr. Zimmerman generally recommends continuing for at least a month if tolerated, before carefully considering a taper.

Treatment at CooperRiis focuses on improving quality of life in line with the person’s goals: optimizing medication(s), reducing symptoms, and providing extensive education and insight-building around the role of cannabis in mental health.

Clinicians work non-judgmentally with residents who may feel betrayed by a substance that once provided comfort or enjoyment and who often strongly resist acknowledging cannabis as a factor in their psychosis.

Marijuana Dependency & Attachment

When residents describe their use, they commonly report benefits such as reduced stress and anxiety or better sleep, and many do experience these gains early on. Over time, however, the effect tends to diminish, leading to escalating dose, potency, or frequency while important areas of life begin to deteriorate.

Despite these harms, there is often a strong emotional and cultural attachment to cannabis, particularly among young people, who may feel that sobriety means giving up a key part of youth and social identity.

So, Is Cannabis Good or Bad for Mental Health?

Dr. Zimmerman acknowledges that many people use cannabis without major problems and that, like alcohol, it can be part of a healthy life for some, while for others, it becomes a source of significant harm. From her perspective, the core issue is not the substance itself but the role it plays in a person’s life: how it affects functioning, relationships, safety, and mental health stability.

Evidence for cannabis as a treatment for mental health conditions is highly conflicted; PTSD has the most positive data, yet there are also many negative studies, and overall, the scientific picture for cannabis as a mental health treatment is, Dr. Zimmerman notes, “not looking promising.”

Full Transcript of Interview with Dr. Amy Zimmerman 

L: What is cannabis induced Psychosis (CIP) in a succinct definition?

DR. Z: It is the experience of psychosis, which can be hallucinations, delusions, gross disorganization in behavior and thought that appears to have been caused by cannabis use.

L: How does that differ from psychosis that is not drug-induced?

DR. Z: In a lot of ways, the symptoms can look pretty similar. The difference often is, with a drug induced psychosis, it can come on much more quickly. Often a lot of folks who experience psychosis as part of a different mental health disorder diagnosis, it is going to grow insidiously over time. Whereas, with substance induced psychosis, you are more likely to get an abrupt or fairly quick onset. And of course, to make the diagnosis of substance induced psychosis, it has to involve someone using the substance.

L: Does cannabis induced Psychosis (CIP) only last as long as the drug itself?

DR. Z: To make a diagnosis of substance induced psychosis, it needs to resolve when the substance is gone, or reasonably within the time that the substance is out of one’s system. If the symptoms do not resolve, then you get into muddier territory.

L: I’m sure that gets complicated when you have someone who is fairly young, and maybe has a history of a thought disorder, like schizophrenia.  So how do you tease out CIP from, say, the early onset of schizophrenia?

DR. Z: Good question. We have these conversations weekly, if not daily. How often do we see residents come to us who are using any substance, but we will just go ahead and say cannabis, heavily, or maybe even not heavily, and they experience a psychotic episode, they go to the hospital, and then they are following up here? Pretty common scenario. And then they come on medications that are managing the psychosis. And that gets blurry too, when they start asking, “How long will I need these medications? If this was really cannabis induced, I should be able to come off these medications if I do not smoke marijuana again. I should be fine.”  

The hard part is, it is rare to be able to give those answers immediately. Some people stumble into the answers when they leave the hospital and they stop their meds, and they are fine. But sometimes it can take a little while for everything to fully resolve and come back to baseline. And that is for the people who are still sober. The textbook would tell you that the drug needs to be entirely out of your system when the symptoms resolve, but in practice, I have seen symptoms last days even after someone has used.  

The advice that many doctors will share is, particularly if the psychosis was hugely disruptive, to maintain the medication that helped pull them out of it for at least a month. I will often go three months, just to be cautious, as long as someone is tolerating the medication. Then if they are sober, doing okay, and seem to be in remission, if I am still working with that person, then we will talk about tapering them off the medication. At least in this setting, because I do not always get that opportunity, because they are usually discharging before that. But that is usually my recommendation, to stay on medication for a period of time, and then gradually taper off.  

If a person is able to come off a medication, and no symptoms have recurred over the course of hours, days, or weeks, there is a pretty good chance that it was a substance induced psychosis. But we also see the folks who taper and come off their meds, and their symptoms seem to come right back. That is when we are more in the territory of cannabis started this, but it is not the only thing. One of my favorite professors used to say, “Genetics load the gun, drugs pull the trigger.” I have found that happens a lot if they have a biological predisposition towards developing psychosis.

L: Who is more likely to experience cannabis induced Psychosis (CIP)?  Obviously, it’s one of the most widely used substances in the United States, illicit or otherwise, other than alcohol and caffeine.  Many people are able to smoke it with regularity without ever having such an episode.  So in your practice, what are the factors that predispose someone to CIP?

DR. Z: Probably the biggest risk factor is a personal history of mood disorder or psychosis.

L: And when you say mood disorder, can you specify what you mean?  Like are we talking about depression, anxiety, or something beyond that?

DR. Z: More like a bipolar disorder, with mood episodes, swinging from hypomanic to manic to depressive. Having depression or other anxiety disorders does not seem to increase the risk nearly as much as having a personal history of a bipolar disorder experience, diagnosis, or other psychosis. Expanding out from that would be a family history of either of those things, particularly if it is in a first degree relative. The data I have seen shows that if you have a first degree relative with schizophrenia, there is an 11 percent chance of developing it yourself, which is huge, like one in ten.  

There is also the potency of the stuff that people use. I tell people, you are not smoking your grandpa’s weed anymore. The stuff that is out now, they have really tailored to increase the THC concentration, versus all of the other cannabinoids in the plant, and it is much more potent and likely to cause psychosis. And then you get into the synthetic stuff, that also can cause a lot more problems for folks.

L: Does age factor in?

DR. Z: I am not sure what the data is. I have tended to see it more in young people in their late teens and early 20s. My perspective, and I am not sure if this is a scientific one, is that if you have been using cannabis for 10 or 20 years and it was going to make you have psychosis, it would have happened early on. So, probably younger ages experience it more often, but also in new onset of use.

L: Can cannabis induced psychosis happen the first time somebody uses [the substance]?

DR. Z: Yes, absolutely.

L: And does the method of administration matter, as in more likelihood of CIP if someone eats it versus smoking it?

DR. Z: Same answer as with the potency. The more potent forms are going to increase your chances, like with the concentrated dabs that people inhale.

L: How much of an increase [of cannabis induced Psychosis (CIP)] have you observed in your career over the past decade since more states have elected to legalize marijuana, either for medicinal or recreational purposes?

DR. Z: I will share that I have not yet lived in a state that has approved cannabis recreationally or medicinally. I feel that providers in legal states are going to be able to tell you a lot more. That being said, I have not seen laws stop that many people when it comes to cannabis. I definitely see it at least once a week, if not daily. It is a really common issue that crosses the path of the psychiatrist, very regularly.

L: You brought up synthetics earlier.  One that we hear a lot about these days because it is available in North Carolina is delta 8.  Would you say that delta 8 is any safer?

DR. Z: It does not appear to be. For all intents and purposes, there are people out there who claim to be connoisseurs of the drug experience. I do not want to doubt their expertise, because I am sure it is there, but from my chair, I have seen delta 8 cause just as much psychosis as delta 9. I have come to view it as a loophole to get marijuana, because it is essentially the same thing.

L: Isn’t that supposed to be less potent though?

DR. Z: That is what they say. I am not sure that I have seen that, at least in the people I am working with.

L: Would you say that cannabis induced Psychosis (CIP) differs significantly from other drug-induced psychoses out there?

DR. Z: To some extent, yes. This is a little off the cuff, but they may be indistinguishable for any given person. In general, if a stimulant is going to cause psychosis, it will tend to cause more of an agitated psychosis, just by its nature. If you are going to use psychedelics, like psilocybin mushrooms or DMT, one of the terms that tends to be used is “floridly psychotic,” which essentially just means they are really deep in it. And so I tend to see more florid psychosis with the psychedelics. That being said, there is a lot of crossover.

L: What would treatment at CooperRiis look like for somebody who may have experienced cannabis induced Psychosis (CIP) and is seeking residential treatment?

DR. Z: Typically, those folks have already had mental health disorder encounters otherwise, unfortunately often with hospitals. By and large, many of them come to us already on some type of antipsychotic medication. The treatment is, as it always is at CooperRiis, helping someone find care that increases their quality of life and is consistent with their goals. We are looking at what the symptoms are, how to ameliorate them, and how to help individuals have their best life.  

As I shared earlier, often my recommendation is going to be continuing an antipsychotic medication for at least a month or more to be on the safe side. In my mind, it is critically important that that medication be tolerable, because if I am going to prescribe you something, my goal is that your life is better, not worse. If you arrive at CooperRiis on a medication that is just really intolerable, I will suggest that we stick with an antipsychotic medication, just find one that is more tolerable for that duration.  

Treatment includes a lot of education, a lot of exploration and insight building. People develop a lot of feelings related to marijuana. It is not uncommon for folks to come in and really struggle to identify that cannabis played a role in their psychosis. They do not want to believe that something that has otherwise brought them enjoyment or comfort in some way has turned around and stabbed them in the back. They will really want to defend it and go back to it. We try to help folks explore it in a non judgmental and supportive way, by asking what role it plays in your life. We ask, what are you hoping to achieve?

L: What is the draw that the residents with whom we work with have towards marijuana?  Is there a diagnosis that seems to be more drawn to using it, and if there’s not one, what are other consistencies that you have noticed among people who resist the idea that cannabis played a role in the decline of their mental health?

DR. Z: Is “youth” a diagnosis? I say that jokingly, but it has become such a cultural thing, and much more widely accepted and supported that people feel like they are giving up on being young if they have to be sober. I have definitely seen that play a role. Any time a resident tells me they smoke cannabis, my first question is, “What does it do for you?” Clearly, it has entered your life for some reason or purpose.  

And they will often say, it helps me manage stress, anxiety, it helps me sleep. And the really hard part is that it does all of these things, for a lot of people, in the beginning. But I have rarely encountered someone who uses a cannabis product regularly for stress, anxiety, or sleep and found it a sustainable option for the management of any of those issues. What they tend to find, and I will describe this to them, and most of them will agree that it was their experience, is that it worked really well in the beginning, it increased their quality of life and their functioning, but over time, it was not doing the job nearly as well.  

They had to go up in dose or potency or frequency, and then it started to become a double edged sword. They needed more to feel not as good as they did in the beginning, and other things start to slip as that adds up. It is really hard to function with cannabis in your system all of the time, and be able to drive and go to work or school. But people still have this emotional attachment to it.

L: From a policy standpoint, laws criminalizing marijuana were repealed and changed because states decided that they created more harm than good.  But it’s clear too that some people are still experiencing real harm from using it.  Is there any middle ground there?

DR. Z: There are plenty of people who use it and enjoy it. It can be part of a healthy life, just like alcohol can be part of a healthy life, or it can cause more problems. The problem is not necessarily the drug. It is the role that it plays in your life. I am not going to comment on pain conditions, or seizure disorders, or other medical conditions where there is evidence for cannabis as a treatment, but really, the evidence is highly conflicted for marijuana use as treatment for any mental health disorder.  

Probably the condition that has the most positive studies would be PTSD, but you are going to find just as many negative studies. But the scientific evidence for cannabis as a treatment for mental health disorders is not looking promising.