Is There Enough Knowledge to Standardize a L. Medicinal Oil Preparation with a High Content of Cannabinoids?

L. medicinal oils are good therapeutic options due to their wide spectrum of pharmacological applications and the easy adjustment of individual doses. The lack of standardization of methodology in the preparation of medicinal oil using the crude extract results in elevated variability of cannabinoid concentration in the final product. The elevated variability impairs the understanding of beneficial and adverse effects related to dose-response pharmacological activities. This study aimed to conduct a review on the current methods of oil preparation present in the literature, to demonstrate the most appropriate methodologies to ensure a product with high content of cannabinoids and terpenes. The decarboxylation stage is essential for the conversion of acid cannabinoids into neutral cannabinoids, which are substances with the highest bioavailability. Lower temperatures for longer periods of time instead of high temperatures in less time are highly recommended to ensure that all the acidic cannabinoids have passed through decarboxylation. For the guarantee of a high terpene content, the separate addition of essential oil to the fixed oil prepared from the crude extract should be considered. Ultrasound-assisted extraction is one of the best performing methodologies because it is cheaper than other techniques, such as supercritical fluid extraction, besides that, ultrasound extraction is effective in short extraction times and uses small amounts of solvent when compared with other techniques. Although the literature about the methods of preparation of medicinal oil is scarce, it is possible to standardize an optimized, low-cost, and effective extractive methodology from the results found in the literature; however, this will depend on new research for methodological validation.