Can cannabis ward off nightmares? Here’s what we know about how weed affects dreams


Dreams – what they mean, where they come from, and why we have them – have fascinated humankind since the dawn of civilization. But while dreams have been studied extensively since then, they remain largely mysterious, and therefore, outside of our control.

This isn’t an issue for most people. While nightmares are common for children, most adults will only experience nightmares on occasion. But for those struggling with reoccurring nightmares, dreams cause severe stress and have a serious impact on sleep quality.

That’s why, when a 2009 study suggested that use of the synthetic cannabinoid nabilone significantly decreased or completely eradicated nightmares for a majority of patients tested, many members of the scientific community were interested.

The study followed 47 patients diagnosed with post-traumatic stress disorder (PTSD) who had been referred to a psychiatric clinic between 2004 to 2006. These patients were experiencing trauma-induced nightmares regularly, despite having each tried antidepressants and hypnotics. Researchers asked these patients to report how their sleep was affected after taking the synthetic cannabinoid. Of those who received it, 72 percent reported their nightmares had either stopped or were significantly less intense.

The researchers concluded, “The results of this study indicate the potential benefits of nabilone, a synthetic cannabinoid, in patients with PTSD experiencing poor control of nightmares with standard pharmacotherapy.”

RELATED: Veterans with PTSD Are Struggling in the Pandemic. Could Cannabis Help?

Multiple studies on the subject have been conducted since then, and though more research needs to be done in order to prove anything definitively, many researchers continue to see THC mitigating the intensity and/or frequency of trauma-related nightmares.

The reason? THC seems to decrease the amount of time a person stays in the rapid eye movement (REM) stage of sleep.

REM sleep is a period of the sleep cycle when the eyes dart around, but don’t send visual information to the brain. It’s believed that memory consolidation happens in REM sleep. It is also when dreaming occurs.

So, by decreasing the amount of time a person spends in REM sleep, THC could be indirectly mitigating a person’s risk of having a nightmare.

“You do hear a lot about people’s dreams kind of disappearing when they use cannabis,” said Dr. Leigh Vinocur, a cannabis clinician and regular contributor to GreenState, “We don’t know the mechanism of why, but we do know that CB1 receptors exist in the brain in many areas that regulate sleep and the processing of memory, like the cerebral cortex and the hippocampus. CB1 receptors bind with THC when we consume cannabis.”

RELATED: Cannabis job growth higher than ever, report finds. Will weed become one of America’s biggest job-creators?

For those struggling with regular, sleep-disrupting nightmares, any therapy with even the potential to curb trauma-induced nightmares could be life-changing.

According to the American Psychiatric Association, 3.5% of U.S. adults deal with PTSD every year. For these patients, trauma-related nightmares can be a nightly occurrence, causing, for many, a major disruption in sleep, sleep-walking or sleep-talking, and an increase in anxiety and insomnia as a result of traumatic memories replayed in a dream. Being able to get a full night’s sleep could significantly improve quality of life for these people.

Nick Etten, co-founder and chairman of Veterans Cannabis Project, an advocacy group and community for veterans using cannabis for medical purposes, says relief from nightmares is a “big component” of why veterans with PTSD have turned to cannabis.

“We’re finding it’s one of the most important tools for veterans with PTSD,” Etten told GreenState. “An overactive brain is not really resting at night. In my own experience, I’ve gone through periods of time where a lot of stuff is getting worked out in dreams and it’s hard. Sure, your brain needs to work some things out in your sleep, but when you’re dealing with nightmares interrupting your sleep consistently, it starts taking a physical toll.”

He added, “This is exactly why we spend so much time advocating for increased access to medical marijuana for veterans, and for more research to be done. Veterans are looking for tools to manage it that don’t have all the negative side effects of the traditional pharmaceuticals the VA has prescribed, and cannabis is doing that for a lot of them.”

Since REM sleep deals with the consolidation of memories as well, decreased REM sleep may have the added benefit of helping PTSD patients forget details of traumatic experiences, Vinocur said. Of course, therapy will help with this, but it’s possible that, for some, the effects of therapy could be supported with cannabis.

“There are still debates by sleep experts on the purpose of dreaming, but it seems that dreams could be consolidating memories and making sense of things that happen throughout the day,” Vinocur said. “So it would seem like there’s potential for THC to help with intrusive thoughts and traumatic memories by decreasing the nightmares. It’s an ongoing area of research, so there’s no definite conclusion on it yet.”

RELATED: TSA won’t search for cannabis, but you can still get in trouble. We asked airport security how to bring medical marijuana on a plane

Vinocur that she always advises patients to focus on therapy if they are struggling to sleep because of a mental health disorder.

“I’m cautiously skeptical when it comes to cannabis – I don’t think it’s the end-all be-all,” Vinocur said. “I recommend to people that they try cannabis, but that they also see a therapist and get some cognitive-behavioral therapy.”

Vinocur also warned that while cognitive-behavioral therapy is a reliable treatment for patients struggling with PTSD, cannabis is not a one-size-fits-all supplement. Though helpful to many people, it can make things worse for others.

There are also significant risks to decreasing REM sleep with cannabis. REM sleep gives the brain a chance to organize and process information. So, by depriving the brain of REM sleep on a consistent basis, you may experience memory loss over time.

“You can think of REM sleep like wiping the slate clean for the new day,” Vinocur explained. “You don’t want to spend your whole life in REM-deprived sleep. It’s important.”

Additionally, some longtime cannabis users report extremely vivid dreams after they stop using it. This is because the REM stage is increasing as a reaction to having been previously suppressed. Because of this withdrawal symptom, Vinocur said, risk of cannabis addiction is high among those using high doses of it to curb nightmares.

“I always tell patients you have to figure out how to deal with stress. You can’t just turn to cannabis all the time,” Vinocur said. “If you are dealing with trauma, you might want to suppress some memories. For short-term use, it seems cannabis can have some therapeutic impact on sleep. But you don’t want to get dependent on it.”


Elissa Esher is an editor at GreenState. Her work has also appeared in The San Francisco Chronicle, The Boston Guardian, Brooklyn Paper, Religion Unplugged, and Iridescent Women. Send inquiries and tips to