The Influence of THC on Sleep and Sleep Stages

Introduction

Tetrahydrocannabinol (THC) has garnered attention for its effects on sleep, with a range of research findings pointing to both potential benefits and drawbacks. In varying doses, THC can affect multiple dimensions of sleep, from the NREM stages to REM, as well as related factors such as melatonin and CB1 receptor signaling. This guide elaborates on how THC interacts with the stages of sleep and compares it with over-the-counter (OTC) medications, other cannabinoids, and prescription drugs such as benzodiazepines, Ambien, and Lunesta.

Stages of Sleep

Sleep consists of four primary stages:

1. Stage 1 (NREM1): the first phase, when you drift in and out of consciousness. It lasts around 5 to 10 minutes.
2. Stage 2 (NREM2): light sleep, with reduced body temperature and heart rate. It lasts about 20 minutes.
3. Stage 3 (NREM3): deep sleep, the stage that matters most for physical restoration. It lasts about 30 minutes.
4. Stage 4 (REM): rapid eye movement sleep, which is critical for memory consolidation and mental restoration. Its duration varies through the night.

These durations describe a typical first sleep cycle. Later cycles shift the balance, with deep sleep concentrated early in the night and REM periods lengthening toward morning.

THC and Sleep Stages

THC has been studied for its effects on these stages, although more research is needed for a conclusive understanding. Systematic reviews of human studies report that THC tends to shorten the time it takes to fall asleep and can reduce REM sleep, with effects that vary by dose, by how long a person has been using cannabis, and by whether the person has a sleep disorder (Gates 2014; Babson 2017).

NREM Sleep by Dose

1. Very low dose: may have negligible effects.
2. Low dose: tends to suppress NREM sleep.
3. Medium dose: can either suppress or enhance NREM sleep, depending on other factors such as individual metabolism and CB1 receptor sensitivity.
4. High dose: often suppresses NREM sleep.
5. Very high dose: generally suppresses NREM sleep and may disrupt sleep architecture.

REM Sleep by Dose

1. Very low dose: may lead to slight REM sleep suppression.
2. Low dose: tends to suppress REM sleep.
3. Medium dose: can either suppress or enhance REM sleep.
4. High dose: suppresses REM sleep.
5. Very high dose: highly suppressive of REM sleep, and may result in REM rebound when THC is stopped.

Melatonin and CB1 Receptors

Cannabinoids, especially in higher doses, can influence the secretion of melatonin and in that way affect sleep patterns. CB1 receptors are also involved: they modulate neurotransmission in ways that influence wakefulness and sleep. In animal studies, signaling through CB1 receptors has been shown to shape the slow cortical rhythms of NREM sleep (Pava 2014), and cannabinoid signaling has been linked to the stability of breathing during sleep (Carley 2002).

Comprehensive Comparison Table

How a Low Dose of CBD Changes the Picture

Small doses of CBD can mitigate some of the disruptive effects of THC on sleep, specifically the fragmentation of NREM sleep seen at high THC doses. The table below, carried over from the companion CED guide that this page now absorbs, adds a low dose CBD column to the same dose ranges so the two cannabinoids can be read side by side.

The mechanism is plausible: CBD acts as a negative allosteric modulator of the CB1 receptor, which means it can dampen how strongly THC activates that receptor (Laprairie 2015). A systematic review of cannabinoid therapies for sleep disorders found that the clinical evidence for CBD alone remains limited and called for larger trials (Suraev 2020), and a study of around-the-clock oral THC in chronic daily cannabis users showed that the sleep effects of THC depend heavily on tolerance and dosing pattern (Gorelick 2013).

Comparisons with Other Medications

1. OTC sleep aids: generally antihistamines, known to reduce REM sleep.
2. Other cannabinoids: CBD may have different effects on REM sleep compared with THC, and in one crossover study CBD taken with THC offset part of the sedative effect of THC (Nicholson 2004). See the companion guide on the influence of CBD on sleep and sleep stages.
3. Benzodiazepines: reduce the time it takes to fall asleep but may also reduce REM and deep sleep.
4. Ambien (zolpidem): targets GABA receptors but may disrupt sleep architecture.
5. Lunesta (eszopiclone): similar to Ambien, acts on GABA receptors and may influence REM sleep.

A meta-analysis of trial data submitted to the FDA found that non-benzodiazepine hypnotics shortened the time to fall asleep by a modest amount compared with placebo (Huedo-Medina 2012), and ramelteon, a melatonin receptor agonist, reduced latency to persistent sleep in a model of transient insomnia (Roth 2005). Those figures are a useful yardstick when weighing THC against prescription options.

Medical Conditions That Call for Caution

The source guides flag these conditions where THC for sleep deserves extra care and a conversation with a clinician:

• Cardiovascular disorders
• Liver diseases
• Sleep apnea
• Mental health disorders such as bipolar disorder and schizophrenia

For guidance tailored to these conditions, patients can consult Dr. Benjamin Caplan at CED Clinic.

What This Does and Does Not Show

The dose by stage table, the dose lists, and the two diagrams are schematic summaries drawn from the review literature, not the output of a single trial. They describe the direction and rough degree of reported effects so that a reader can see the pattern at a glance. They do not report measured minutes of NREM or REM sleep at a given milligram dose, and they do not replace a sleep study or an individualized plan. Where controlled data exist, they are cited in the text above.

References

1. Babson KA, Sottile J, Morabito D. Cannabis, Cannabinoids, and Sleep: a Review of the Literature. Current Psychiatry Reports. 2017;19(4):23.
2. Nicholson AN, Turner C, Stone BM, Robson PJ. Effect of Delta-9-tetrahydrocannabinol and cannabidiol on nocturnal sleep and early-morning behavior in young adults. Journal of Clinical Psychopharmacology. 2004;24(3):305-313.
3. Gates PJ, Albertella L, Copeland J. The effects of cannabinoid administration on sleep: a systematic review of human studies. Sleep Medicine Reviews. 2014;18(6):477-487.
4. Huedo-Medina TB, Kirsch I, Middlemass J, Klonizakis M, Siriwardena AN. Effectiveness of non-benzodiazepine hypnotics in treatment of adult insomnia: meta-analysis of data submitted to the Food and Drug Administration. BMJ. 2012;345:e8343.
5. Roth T, Stubbs C, Walsh JK. Ramelteon (TAK-375), a selective MT1/MT2-receptor agonist, reduces latency to persistent sleep in a model of transient insomnia related to a novel sleep environment. Sleep. 2005;28(3):303-307.
6. Carley DW, Paviovic S, Janelidze M, Radulovacki M. Functional role for cannabinoids in respiratory stability during sleep. Sleep. 2002;25(4):391-398.
7. Pava MJ, den Hartog CR, Blanco-Centurion C, Shiromani PJ, Woodward JJ. Endocannabinoid modulation of cortical up-states and NREM sleep. PLoS One. 2014;9(2):e88672.
8. Laprairie RB, Bagher AM, Kelly ME, Denovan-Wright EM. Cannabidiol is a negative allosteric modulator of the cannabinoid CB1 receptor. British Journal of Pharmacology. 2015;172(20):4790-4805.
9. Suraev AS, Marshall NS, Vandrey R, et al. Cannabinoid therapies in the management of sleep disorders: A systematic review of preclinical and clinical studies. Sleep Medicine Reviews. 2020;53:101339.
10. Gorelick DA, Goodwin RS, Schwilke E, et al. Around-the-clock oral THC effects on sleep in male chronic daily cannabis smokers. American Journal on Addictions. 2013;22(5):510-514.
11. Schierenbeck T, Riemann D, Berger M, Hornyak M. Effect of illicit recreational drugs upon sleep: cocaine, ecstasy and marijuana. Sleep Medicine Reviews. 2008;12(5):381-389.

This page is a reconstruction of the original CaplanCannabis.com guides. The book that grew out of that series, The Doctor-Approved Cannabis Handbook, is available here.

Frequently Asked Questions