**5. Overall conclusion**

This chapter has identified a consensus in the scientific literature that specific phytochemicals (CBD, linalool, α-pinene, β-caryophyllene, flavonoids and anthocyanins) found in cannabis plants are beneficial for cognition and brain health in a number of disease states. These compounds are psychoactive as they alter the brain to effect behaviour, and there is some evidence that they can differentially affect healthy individuals (e.g., CBD has no cognitive benefits and linalool has detrimental effects on cognition in healthy subjects). Therefore, societal consideration of 'medicinal cannabis' as a true medicine is necessary, that is, prescribed for patients who require treatment of a clinically diagnosed illness. Further research is needed to inform optimal prescription for treating specific illnesses, including dose, route of administration, long-term clinical efficacy, safety and side effects. There is some evidence to support the existence of an 'entourage effect'—such synergism could arise from a multitarget approach. The united benefits of specific terpenes and flavonoids could boost the therapeutic potential of CBD to improve cognition in disease states that manifest impairment; we are currently investigating these synergies in my laboratory. An other exciting future area of investigation is the identification of select cannabis phytochemical profiles that will treat specific illnesses with optimal efficacy. Following this, efforts towards standardising horticultural and cannabis plant processing practices to ensure optimal and reproducible medicines can be directed towards a proven goal—a translational interface between medical science and horticulture.
