Study Aims to Optimize CBD Absorption and Solubility for Enhanced Therapeutic Use

A recently published study (1) aimed to improve the solubility and permeability of oral CBD in order to increase therapeutic effects, including pain and anxiety relief and inflammation reduction, when treating conditions such as epilepsy, multiple sclerosis, and Alzheimer’s. As noted in the study’s abstract, the poor water solubility, low GI permeability, and chemical instability of CBD reduce its potential benefits. Researchers at the University of South Australia (UNISA) sought to create a CBD–phospholipid complex as an improved delivery system of CBD. The study, “Optimising Cannabidiol Delivery: Improving Water Solubility and Permeability Through Phospholipid Complexation,” was published in March 2025 in the International Journal of Molecular Sciences.

Common CBD delivery systems present problems such as varying absorption and influence by food intake and gastrointestinal conditions, which impact the therapeutic effects of the cannabinoid for patients. 

“For this reason, a number of different formulations have been explored, including the production of synthetic CBD, self-emulsifying delivery systems, and encapsulating CBD in gelatine matrix pellets, but all of them have only resulted in minor improvements in bioavailability,” stated lead researcher Professor Sanjay Garg in a news release from UNISA (2).

Using phospholipids could help move the drug across biological barriers, enhancing absorption and helping reduce dosage requirements of the CBD. In this study, the researchers developed and tested aCBD-PLC to achieve this goal.

Highlighted results include (1):

• Dissolution studies revealed significantly enhanced release rates for CBD-PLC—44.7% at 2 hours and 67.1% at 3 hours, compared to 0% for pure CBD and 7.2% for a physical mixture
• Cellular uptake studies showed that at 30 µM, CBD-PLC exhibited 32.7% higher apparent permeability coefficients, nearly doubling at 40 µM compared to pure CBD.

Ultimately, the results indicated a six-fold increase in solubility and dissolution of the CBD-PLC, plus a sustained drug release.

“Improved bioavailability means that lower doses can achieve the same therapeutic effect, potentially reducing side effects and making treatment more cost effective,” added study author Thabata Muta.

Tests also confirmed its safety and performance under different temperatures over 12 months. The methodology used to create the CBD-PLC could also be used to improve the solubility of other unstable drugs, the conclusion noted.

References

1. Muta, T.; Khetan, R.; Song, Y.; Garg, S. Optimising Cannabidiol Delivery: Improving Water Solubility and Permeability Through Phospholipid Complexation. Int. J. Mol. Sci. 2025, DOI: 10.3390/ijms26062647.
2. University of Southern Australia. New cannabis formula will help epilepsy, multiple sclerosis sufferers https://www.unisa.edu.au/media-centre/Releases/2025/new-cannabis-formula-will-help-epilepsy-multiple-sclerosis-sufferers/ (accessed March 27, 2025).