Cannabis Improves Sleep in People with Depression — But Not in Others
Cannabis has long been seen by many — especially the users themselves — as a natural remedy for sleepless nights. However, the scientific community has grappled with conflicting evidence. While some studies suggest cannabis might help with sleep, others show it could actually worsen sleep quality.
A study published in Addiction Journal in 2025 offers an intriguing explanation: cannabis’s impact on sleep may depend heavily on one’s mental health status.
The Surprising Research
Researchers at University of Southern California followed nearly 2,000 young adults, aged 20 to 23, over the course of a year to understand how cannabis use affects sleep. They asked participants how often they used cannabis, ranging from never to almost daily, and then checked in several months later to see how their sleep had changed. The study also took into account their mental health, asking whether they had symptoms of anxiety or depression, and how well they were sleeping at the start.
The results were surprising. For young adults who were dealing with anxiety or depression and had trouble sleeping, frequent cannabis use (20 or more days a month) measurably improved sleep quality over six months. But those without mental health challenges, who regularly used cannabis, actually faced more sleepless nights and worsening sleep problems.
In other words, cannabis seemed to help those who were already struggling, but it had the opposite effect for those who weren’t.
Claire Walsh, a PhD student at USC who led the study, agreed that while many people see cannabis as a sleep aid, the science is not so clear: “Part of the reason could be because individual factors like mental health play a role in how cannabis use affects sleep.”
The Endocannabinoid Puzzle
So how exactly does cannabis interact with our sleeping patterns? It may have to do with the body’s endocannabinoid system — a network that helps regulate things like mood, appetite, pain, and sleep. THC, the main psychoactive component in cannabis, interacts with this system, but we’re still learning exactly how it impacts sleep.
Some evidence suggests THC may help people fall asleep faster, but over time, it could lead to shorter, more disrupted sleep, especially for those who use THC edibles often. Other compounds like CBD (a non-psychoactive part of the cannabis plant) or Nabilone (a synthetic cannabinoid) seem more promising. For instance, Nabilone may reduce nightmares linked to PTSD and help people with chronic pain sleep better.
Cannabis may impair sleep quality particularly by decreasing the duration of REM sleep — the stage when most dreaming occurs. REM sleep plays a vital role in memory processing, emotional regulation, and brain restoration. That’s why people who use cannabis regularly often report dreaming less — and why some experts worry that long-term cannabis use could subtly affect cognitive and emotional health over time.
Still, this potential disruption might not impact everyone equally. For people already suffering from mental health conditions, especially those with overactive thoughts or trauma-related insomnia, reducing REM might not feel like a loss — it might feel like relief.
What the Science Says About Cannabis, Depression, and Sleep
This isn’t the only research suggesting that cannabis might be helpful for people with mental health struggles. A recent clinical trial, for example, looked at patients with post-traumatic stress disorder (PTSD) who used vaporized cannabis and found moderate improvements in symptoms — including better sleep, fewer nightmares, and reduced hyperarousal.
Similar results have been seen in studies focused on people with anxiety-related insomnia, chronic stress, or depression. While these findings are promising, scientists agree that more rigorous, long-term research is needed. Many existing studies rely on self-reported data, and cannabis strains and dosages can vary widely. For cannabis to become a trusted sleep aid, future studies will need to use standartized doses, carefully chosen strains, and better controls to track outcomes over time.
What Does This Mean for People with Depression?
If you live with anxiety or depression and struggle with sleep, medical cannabis might offer some relief. Sleep and mental health are deeply connected — especially when it comes to depression. In fact, trouble sleeping is one of the most common symptoms of depression, and for many people, it’s the first sign that something’s wrong. Falling asleep can feel impossible when your mind is stuck in a loop of worries or hopeless thoughts, and waking up exhausted only makes it harder to cope the next day.
The relationship also goes both ways: poor sleep can increase the risk of developing depression, and depression can make sleep harder to restore. It becomes a vicious cycle, where each problem feeds the other — and breaking that cycle is often one of the first goals in treatment.
This is where cannabis enters the picture. If it helps calm intrusive thoughts or reduce nighttime anxiety, it may offer a temporary break in the sleep–depression loop. That’s likely why the USC study found improved sleep among cannabis users who had mental health symptoms: they had more to gain. But relief doesn’t necessarily mean healing — and using cannabis to manage sleep without addressing the root of depression can come with its own risks.
Self-Medicating with Cannabis: A Risky Sleep Strategy
The USC study underscores a crucial point: the effects of cannabis on sleep aren’t universal — they depend heavily on individual circumstances. For those with depression or anxiety, it may offer some relief, at least in the short term. But for others, especially those without mental health challenges, or with different mental conditions, using cannabis as a sleep aid can make things worse.
This nuance is especially important when people self-medicate. Without clinical oversight, it’s easy to misjudge dosage, frequency, or strain. What begins as a way to relax or “take the edge off” can spiral into disrupted sleep patterns or deeper emotional imbalances.
In short, cannabis may seem like a quick fix, but your mental health status, how often you use it, and why you turn to it all shape the outcome. Approaching it mindfully — and ideally with professional support — is key to avoiding unintended consequences.
And like any sleep aid, cannabis comes with risks. Regular use can lead to dependence, meaning you may struggle to sleep without it. If someone stops suddenly, they might experience withdrawal symptoms, including rebound insomnia, irritability, or vivid dreams.
Guided Use, Better Outcomes
With the right guidance, medical cannabis can be part of a balanced sleep toolkit. If you’re considering it, reach out to a provider who understands both the science and your personal context, can guide the process, monitor side effects, and make adjustments if needed.
Experts recommend a “start low, go slow” approach: begin with a low dose, opt for strains known for their calming effects, and avoid smoking if possible, since inhaling any kind of smoke can irritate the lungs. Vaporizing, capsules, or tinctures offer more consistent dosing and fewer respiratory risks. Edibles may seem appealing, but they can take longer to kick in and be harder to dose correctly, which can lead to a rough experience — especially at night.
Tracking how you feel — with or without cannabis — is also a key part of making informed choices. A simple sleep journal, notes on your phone, or even a wellness app can help you and your provider see what’s working and what’s not. Mental health is deeply individual — and so is the path to improving it.
