A new study published in Biomolecules & Therapeutics found that a combination of cannabidiol (CBD) and L-theanine improved sleep-related outcomes in an animal model of caffeine-induced sleep disruption.
The study was conducted by researchers from Jeonbuk National University and Sahmyook University.
For the study, researchers examined the individual and combined effects of CBD and L-theanine, a compound commonly found in tea, using a mouse model of stimulant-related sleep disturbance. Mice were given CBD and L-theanine orally at different ratios before undergoing pentobarbital-induced sleep testing.
Researchers found that the combination of CBD and L-theanine significantly reduced the amount of time it took the mice to fall asleep, while also increasing total sleep duration, compared with single treatments under sleep-disturbed conditions.
The study found evidence of a synergistic interaction at lower doses, meaning the combination appeared to produce a stronger effect together than either substance alone. However, that same interaction was not observed at higher doses under normal conditions.
Researchers also examined several neurochemical markers associated with sleep regulation, including serotonin, melatonin and gamma-aminobutyric acid, commonly known as GABA. According to the study, CBD increased serotonin levels in a dose-dependent manner, while L-theanine increased serotonin at lower doses.
Combination treatment was associated with increased serotonin and melatonin levels, both of which rose by more than 40% compared with the caffeine-treated group. Cortical GABA levels were also elevated following combination treatment.
The researchers concluded that co-administering CBD and L-theanine improved sleep-related outcomes and was associated with neurochemical changes, although they noted that the precise mechanisms still need to be determined.
They said the findings suggest CBD and L-theanine co-administration may offer a potential alternative approach for managing stimulant-induced sleep disturbances.
The study was conducted in mice, meaning further research, including human trials, would be needed to determine whether the findings apply to people.
