Cannabidiol (CBD), a constituent of herbal cannabis has attracted much interest recently as a promising medicine. After being discovered in the early 1970s it was quickly established that CBD has anti-convulsant and anxiolytic properties in animal models and in humans and was safe. Work in the 1980s and early 1990s suggested CBD had anti-psychotic properties and could be an effective treatment for schizophrenia.
This was in stark contrast to the other main ingredient of the cannabis plant, THC, which was attracting increasing concern, due to adverse effects on mental health. In the last decade or so many other properties of CBD have been characterised. The 2 main characteristics from the therapeutic perspective are that CBD has potent anti-inflammatory properties and is a neuroprotectant. There has been considerable excitement that CBD appears to protect, not just neurons, but heart muscle from injury. Several groups in the US and UK are pursuing this line which has massive implications for clinical practice. Perhaps even more dramatic is recent work from Mechoulam’s lab which suggests that CBD can restore normal pancreatic functioning in models of type 1 diabetes. The list of putative indications for CBD include…
- temporal lobe epilepsy
- Rheumatoid arthritis
- Type 1 diabetes
- Head injury
- Acute myocardial infarction
If CBD has the potential to be so useful clinically, why has itnot already translated to the clinic? The answer is that CBD production needed bulk quantities of raw plant material for tablets of sufficient ‘strength’ to offset low GI absorption. That process was too costly ($100/g) without the support of major pharma. In the UK, GW pharmaceuticals elected to grow hemp on a large scale whilst developing an inhalational spray for drug delivery. Their preparation Sativex, which contains THC: CBD (50:50) is licensed in Canada for the treatment of spasticity in MS and for cancer pain.
In the future we will be investigating the possibilities of synthesising the raw CBD molecule, thus circumventing the problems associated with the growing of the raw plant material.