THC interacts with the endocannabinoid system, which plays a regulatory role in your sleep-wake cycle. Research suggests that THC can:
- Reduce sleep onset latency: Fall asleep faster. THC appears to decrease the time it takes to transition from wakefulness to sleep.
- Increase deep sleep: Some studies show THC can increase time spent in slow-wave sleep (deep sleep), the most physically restorative sleep stage.
- Reduce REM sleep: THC tends to decrease REM sleep, which is the dream stage. This can be beneficial for people with PTSD-related nightmares, but means you may dream less.
The key is dose. Low to moderate doses of THC tend to promote sleep, while high doses can actually increase wakefulness and anxiety — the opposite of what you want.