The most famous cannabinoid of all is delta-9-tetrahydrocannabinol, more commonly known as THC. In addition to the recreational feeling of ‘getting high’, THC is also responsible for many of the medicinal effects of cannabis. This includes, among others, reduction of nausea, vomiting, pain and muscle spasms, and improvement of sleep and appetite..

Another cannabinoid that receives a lot of scientific attention is cannabidiol, or CBD. It has medicinal effects but does not make a person feel “high”. To the contrary, CBD actually reduces some of the unwanted effects that are caused by higher doses of THC. Studies indicate that CBD could be effective in easing the symptoms of various difficult-to-control conditions, such as rheumatoid arthritis, diabetes, PTSD, anxiety disorder, and antibiotic-resistant infections. Other examples of medicinal cannabinoids include cannabigerol (CBG) which has potent anti-inflammatory effects, and tetrahydrocannabivarin (THCV) which is being studied for treating epilepsy and Parkinson’s disease.

The chemical structures of these cannabinoids are shown in figure 2-2. Because of their very different therapeutic properties, the specific mix of cannabinoids present in a cannabis flower has a major impact on the medicinal properties it may cause. Terpenes display a wide range of effects that modulate the effects of THC.