Acording to the study,"Cannabis has a potential for clinical use often obscured by unreliable and purely anecdotal reports".
The most important natural cannabinoid is the psychoactive Tetrahydrocannabinol (A 9 -THC),Cannabidiol (CBD) and Cannabigerol (CBG). Not all the observed effects can be ascribed to THC, and the other constituents may also modulate its action. For example CBD reduces anxiety induced by THC. A standardised extract of the herb may be therefore be more beneficial in practice and clinical trial protocols have been drawn up to assess this.
The mechanism of action is still not fully understood, although can- nabinoid receptors have been cloned and natural ligands identified.
-Therapeutic Applications of Cannabinoids
Probably the most important applications for cannabinoids at present tend to be diseases where the existing treatments are not wholly satisfactory, for example, neurological conditions like multiple sclerosis (MS), and chronic intractable pain and drug-induced emesis. There may be a place for cannabinoids in glaucoma, asthma and cardiovascular conditions, although clinical use in these indications is some way in the future.
The possibility of using cannabinoids in psychiatric illness ismore complex since it is often assumed that cannabis is more likely to cause rather than alleviate psychiatric.
Cannabis is frequently used by patients with multiple sclerosis (MS) for muscle spasm and pain, and in an experimental model of MS low doses of cannabinoids alleviated tremor. Most of the controlled studies have been carried out with THC rather than cannabis herb and so do not mimic the usual clincal situation. Small clinical studies have confirmed the usefulness of THC as an analgesic.CBD and CBG also have analgesic and antiinflammatory effects, indicating that there is scope for developing drugs which do not have the psychoactive properties of THC.
Cannabinoids are effective in chemotherapy, induced emesis. Also, anecdotal reports of cannabis use include case studies in migraine and Tourette's syndrome, and as a treatment for asthma and glaucoma.
Patients taking the synthetic derivative nabilone for neurogenic pain actually preferred cannabis herb and reported that it relieved not only pain but the associated depression and anxiety. 'Nabilone' has been licensed for this use for several years and the synthetic cannabinoid HU211,'Dexanabinol' is undergoing trials as a protective agent after brain trauma.
Apart from the smoking aspect, the safety profile of cannabis is fairly good. However, adverse reactions include panic or anxiety attacks, which are worse in the elderly and in women, and less likely in children. Although psychosis has been cited as a consequence of cannabis use, an examination of psychiatric hospital admissions found no evidence of this, however, it may exacerbate existing symptoms.
-Future Research and Applications
Future clinical development will focus on either the use of the whole cannabis extract or the production of individual cannabinoids. With the plant extract, an advantage is that anecdotal evidence exists to justify further investigation. Several components of the mixture are known to be active and in some cases the combination gives a superior result to that of a single compound.
However, natural materials are highly variable, because of genetic factors and growing and processing conditions, and multiple components need to be standardised to ensure reproducible effects and pharmacokinetics which are more complicated with a mixture. Microbial contamination may need to be assessed and dealt with. Pure compounds do not have these particular disadvantages but as novel entities their properties may be completely different, and need to be inves- tigated more thoroughly before entering phase I trials. Both lines of research are valid, and after many years of being dismissed, perhaps this fasci- nating but maligned plant will fulfil its potential.
Source: https://archive.org
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