A Cannabis Oil With THC and CBD Improved Sleep in 60% of Insomnia Patients in a Placebo-Controlled Trial | Research

The takeaway

In a randomized crossover trial of 29 adults with clinical insomnia, a THC/CBD cannabis oil (10mg/15mg per ml) led to 60% of participants no longer qualifying as clinical insomniacs, with a 30% increase in midnight melatonin and 21 extra minutes of light sleep per night.

People with insomnia, sleep medicine clinicians, medical cannabis researchers.

60% of participants no longer classified as clinical insomniacs after cannabis oil

What the researchers found

60% of participants no longer classified as clinical insomniacs after 2 weeks of cannabis oil. Midnight melatonin levels increased 30% in the active group vs. a 20% decline in placebo (P=0.035). Light sleep increased by 21 minutes per night compared to placebo (P=0.041). Overall sleep quality improved by up to 80% (P=0.003).

Why it matters

This is one of few placebo-controlled RCTs of cannabis for insomnia. The melatonin finding is particularly interesting because it suggests cannabis may work through the body's natural sleep-signaling pathway rather than just sedation.

The numbers in context

N=29 completers. 60% no longer clinical insomniacs. Melatonin: +30% active vs. -20% placebo (P=0.035). Light sleep: +21 min/night (P=0.041). Sleep quality: up to 80% improvement (P=0.003). Daily functioning improved (P=0.032).

How the study worked

Randomized double-blind placebo-controlled crossover trial over 6 weeks (2-week intervention, 1-week washout, crossover). 29 participants with self-reported clinical insomnia. Active oil: 10mg/ml THC + 15mg/ml CBD, titrated 0.2-1.5 ml/day.

What this study cannot tell us

Small sample (N=29). Short 2-week intervention period. Self-reported insomnia (not polysomnography-diagnosed). Period effect with more pronounced Phase 2 results. Loss of blinding noted by authors. Fitbit tracker has limitations compared to polysomnography.

How to read the evidence

Randomized double-blind placebo-controlled crossover design, though limited by small sample and short duration.

When this study was published

Published in 2023.

The bigger picture

Insomnia affects up to 30% of the general population, and many people already use cannabis for sleep without clinical evidence to support it. This small but well-designed trial adds controlled evidence, though the period effect and loss of blinding in Phase 2 complicate interpretation.

Questions still open

Would the sleep benefits persist beyond 2 weeks, or would tolerance develop?
Is the melatonin increase a direct effect of cannabinoids or secondary to improved sleep?

Common questions

Does cannabis help with insomnia?

In this placebo-controlled trial, a THC/CBD cannabis oil helped 60% of participants no longer meet criteria for clinical insomnia after 2 weeks, with measurable increases in melatonin and sleep time.

How did the cannabis oil affect melatonin?

Midnight melatonin levels increased by 30% in the cannabis group while declining 20% in the placebo group, suggesting cannabis may support the bodys natural sleep signaling.

Read the original research

Medicinal cannabis improves sleep in adults with insomnia: a randomised double-blind placebo-controlled crossover study.

Journal of sleep research, 32(3), e13793

View on PubMed ↗Publisher’s paper ↗

Citation

Ried, Karin; Tamanna, Tasnuva; Matthews, Sonja; Sali, Avni. (2023). Medicinal cannabis improves sleep in adults with insomnia: a randomised double-blind placebo-controlled crossover study.. Journal of sleep research, 32(3), e13793. https://doi.org/10.1111/jsr.13793