Cannabis, CBD, and Sleep

Medically Reviewed by Brunilda Nazario, MD on July 27, 2021
Written by Keri Wiginton
6 min read

If you’re one of the millions of people who have trouble sleeping, you may have considered a cannabis compound, such as CBD. Some say cannabis compounds are helpful, but more research is needed. And they might not be legal, depending on where you live. Look up the laws to know what’s allowed.

Also known as marijuana, there’s growing interest in the health benefits of cannabis, specifically cannabis compounds. Two cannabinoids that get a lot of attention are:

  • Tetrahydrocannabinol (THC). The compound in cannabis that makes you feel high. Human-made versions are used to ease nausea and vomiting from cancer treatment.
  • Cannabidiol (CBD). A compound in cannabis said to have anti-inflammatory and anti-seizure properties. It does not make you feel high.

Research results on cannabis and sleep are mixed. So far, there haven’t been many controlled studies to show that THC, CBD, or a combination of both can boost sleep quality, says Bhanuprakash (Bhanu) Kolla, MD. He’s an associate professor of psychiatry and psychology and a consultant for Mayo Clinic’s Center for Sleep Medicine in Rochester, MN.

But some studies show promise. That includes a small one on dronabinol, a human-made version of medical THC. Early research shows it might help with obstructive sleep apnea. But “at this point, we do not recommend the use of cannabis products for treatment of sleep apnea or other sleep disorders,” Kolla says.

Ryan Vandrey, PhD, professor of psychiatry and behavioral sciences at Johns Hopkins University in Baltimoe, looks at how cannabis use affects sleep. He says there’s evidence that THC can help you fall asleep faster in the short-term. But “there’s a big gap in our knowledge” for how cannabis affects overall sleep quality long-term or if it can help people with sleep disorders.

Michelle Sexton, ND (naturopathic doctor), assistant adjunct professor in the department of anesthesiology at the University of California, San Diego, helps people use cannabis to manage certain health conditions. She says those who use THC to ease pain often report longer sleep time. “They’re not waking as much,” she says.

Sexton sees some real-world benefits from THC products. But when it comes to cannabis research on sleep, “the body of literature is pretty small.”

There’s some evidence that nabilone -- another human-made form of cannabis -- might help ease sleep problems related to posttraumatic stress disorder (PTSD). Vandrey says people with PTSD often say they have fewer nightmares when they use cannabis. “A lot of folks report not remembering dreams,” he says.

A lot more research is needed to know if CBD can help with sleep. Vandrey says people who use it to manage other health conditions -- anxiety, pain, epilepsy -- often say their sleep gets better. But he says we don’t know if that’s from the CBD itself or because the compound helps in other ways.

“We can try to piece together a story,” Vandrey says. “But it’s really an incomplete picture at this point.”

Your brain and body get used to the chemicals in cannabis or other drugs. You’ll have to use a higher dose to get the same effects. With repeated use, cannabis might not help you sleep as well, or you might find it hard to snooze on your own.

“What commonly happens is people get into a pattern of using cannabis -- whether it’s a high THC or high CBD hemp product -- on a daily basis for an extended period of time,” Vandrey says. “Then, when they go one night without it, they can’t sleep.”

You’re not likely to overdose on THC or CBD, but here are some things to think about:

  • Withdrawal. Long-term cannabis use can cause sleep problems when you try to quit. Vandrey says that includes insomnia and the return of vivid dreams or nightmares.
  • Dizziness or balance problems. If you have to get up to pee at night, Sexton says to give yourself a minute to see if you feel stable. If you have a walking aid, make sure you use it.
  • Trouble thinking clearly. Heavy cannabis use is linked to problems with memory, learning, and attention.
  • Health problems. Smoking any substance can hurt your lungs, heart, or blood vessels.
  • Substance misuse. Cannabis is less addictive than alcohol or opioids. But people who use it every day might get a cannabis use disorder. Tell your doctor if you want to stop but can’t. They’ll help you quit.

Don’t use cannabis products if you’re pregnant or breastfeeding. The drug could affect your baby.

Kolla says it’s OK to use CBD if you think it helps your sleep. He says there isn’t any data to show that it’s harmful. But keep in mind these products aren’t regulated by the FDA. There’s no way to know exactly what you’re getting. “A lot of times, CBD can be contaminated with THC and there are potentials for drug interactions,” Kolla says.

Vandrey says CBD can interact with multiple biological systems in the body. But he says there’s no research to know how long-term use will affect those systems. Until we know more, “keep use of these products controlled in some way,” he says. “You use them for a couple of weeks and then you stop.”

There isn’t an official “dose” that works for everyone. Always read the product label for instructions. Even better, talk to a health care professional before you try THC or CBD. Tell them if you have other health problems or you take any other medication.

Sexton doesn’t suggest CBD as a sleep aid. She says it can have an “alerting” effect for some people. Here are some of her tips for how and when to use THC:

Look for “indica” on the label. There isn’t one “nighttime” strain. You’ll need to try different kinds to see what works best for you. Though, she says something labeled indica might be more sedating.

Start with a low dose. Sexton says a 2-milligram dose is a good place to start. If you’re new to THC, you might want to go lower. More might give you unwanted side effects. “You might wake up in the middle of the night paranoid with your mind racing,” Sexton says.

Use oral THC. Drop it in the back of your mouth and swallow. “I typically stick with the oral dose because of how long it lasts, and it comes on more slowly,” she says.

The effects kick in after 1 to 3 hours, she says, and could last for 6 to 8 hours. If you try a dose that doesn’t help, “wait it out.” Sexton says you can raise your dose by 50% the next night.

  • If you have trouble staying asleep. Take an oral dose right as your “head hits the pillow.”
  • If you have trouble falling asleep. Take an oral dose 1 to 2 hours before bed.

Don’t go above 10 milligrams. A larger amount might raise your odds of poor sleep. “We don’t know if (THC) is disrupting sleep architecture at those higher doses,” Sexton says.

Ask about nondrug ways to get a good night’s rest. “My sleep expert colleagues will always say behavioral treatments are superior to pharmacological treatments,” Vandrey says.

Sexton urges good sleep hygiene. But she also tries to find any hidden problems. Here are some questions she asks:

  • Do you exercise at 8 p.m.?
  • Do you drink green tea with dinner?
  • Do you take your B vitamins at night?
  • Are you stressed or anxious?
  • Is your sleep trouble linked to hormonal changes?

No detail is too small and could help your doctor figure out what’s triggering your sleep issues.