The main psychoactive component of Cannabis/Marijuana includes delta-9 tetrahydrocannabinol, THC for short, also known by its International Nonproprietary Name (INN) as dronabinol. The unsaturated bond in the cyclohexene ring is located between C-9 and C-10 in the more common dibenzopyran ring numbering system. They are four stereoisomers of THC, but only the (-)-trans isomer occurs naturally.
The fully systematic name for this THC isomer is (-)-(6aR,10aR)-6,6,9-trimethy-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol. Two related substances, 9tetrahydrocannabinol-2-oic acid and 9tetrahydrocannabinol-4-oic acid (THCA), also present in cannabis, sometimes in large amounts. During smoking THCA is partly converted to THC. The active isomer 8-THC, in which the unsaturated bond in cyclohexene ring is located between C-8 and C-9, is found in much smaller amounts.
Molecular formula: C21H30O2 Molecular weight: 314.4 g/mol
Other closely related substances that occur in cannabis include cannabidiol (CBD) and, in aged samples, cannabinol (CBN), both of which have quite different pharmacological effects to THC. Other cannabivarins and cannabichromenes; they are collectively known as cannabinoids. Unlike many psychoactive substances, cannabinoids are not nitrogenous bases.
Physical Forms of Cannabis
Cannabis sativa is dioecious – they have separate male and female plants. THC is largely concentrated around the flowering parts of the female plant, while the leaves and male plants have less. The stalks and seeds contain close to none. Imported herbal cannabis occurs as compressed blocks of dried brown vegetable matter comprising the flowering tops, leaves, stalks and seeds of Cannabis Sativa. Cannabis resin is a compressed solid made from the resinous parts of the plant, usually produced in 250 g block, many of which carry a brandmark impression. Cannabis (hash) oil is a solvent extract from cannabis or cannabis resin which is a dark viscous liquid. It can be a clear, amber or gold glassy solid when cold, which becomes viscous and sticky if warmed.
Origin
Herbal cannabis is mostly grown and distributed in West Africa, the Caribbean or South-East Asia. Together with tobacco, alcohol and caffeine, it is one of the most widely consumed drugs throughout the world and has been used as a drug and a source of fibre since historical times.
Imported herbal cannabis occurs as compressed blocks of dried brown vegetable matter comprising the flowering tops, leaves, stalks and seeds of Cannabis Sativa. Cannabis resin is a compressed solid made from the resinous parts of the plant, usually produced in 250 g block, many of which carry a brandmark impression. Cannabis (hash) oil is a solvent extract from cannabis or cannabis resin which is a dark viscous liquid. It can be a clear, amber or gold glassy solid when cold, which becomes viscous and sticky if warmed. Cannabis resin or cannabis oil are usually consumed directly or vaporised to be inhaled. Intensive indoor cultivation has become widespread in Europe and elsewhere. This is based on improved seed varieties and procedures such as artificial heating and lighting. Hydroponic cultivation in nutrients solutions and propagation of cuttings of female plants. All these have lead to high production of flowering material.
Pharmacology of cannabis is complicated by the presence of a wide range of cannabinoids. THC overactivates certain brain cell receptors. At short term small dose, cannabis produces euphoria, relief of anxiety, sedation, drowsiness, impairs thinking and coordination. In some respects, the effects are similar to those caused by alcohol. Anandamide has been identified as the endogenous ligand for the cannabinoid receptor and has pharmacological properties similar to those of THC. When cannabis is smoked, THC can be detected in plasma within in seconds of inhalation; it has a half-life of 2 hours. Following smoking of the equivalent of 10-15 mg over a period of 5-7 minutes, peak plasma levels of 9THC are around 100g/L. It is highly lipophilic and widely distributed in the body. As an aromatic terpenoid, THC has a very low solubility in water, but good solubility in most organic solvents, specifically lipids and alcohol. Two active metabolites are formed: 11-hydroxy-9-THC and 8-hydroxy-9-THC. The first is further metabolised to 9-THC-11-oic acid. Two inactive substances are also formed –8-hydroxy-9-THC and 8, 11-dihydroxy-9-THC and many other minor metabolites, most of which appear in the urine and faeces as glucuronide conjugates. Some metabolites can be detected in the urine for up to 2 weeks following smoking and ingestion. There is little evidence for damage to organ systems among moderate users, but consumption with tobacco carries all of the risks of that substance like breathing illnesses. Most interest in the adverse properties of cannabis centers on its association with schizophrenia, although it is still unclear if there is a causative relation between mental health and cannabis. Fatalities directly attributable to cannabis are rare. Cannabis overdoes does not lead to death but can cause some very uncomfortable side effects, such as unease and shaking and, in rare cases, an extreme psychotic reaction. There is also possible harm to fetus’s brain in pregnant women.
Cannabis and cannabis resin can be positively tested using low power microscopy, where the appearance of glandular trichomes and cystolithic hairs is diagnostic. The Duquenois test is considered to be specific for cannabinols. It is based on the reaction of cannabis extracts with p-dimethylbenzaldehyde. This produces a violet blue coloration that is extractable into chloroform. The mass spectrum of THC shows major ions at m/z= 299, 231, 314, 43, 41, 295, 55 and 271. Using gas chromatography, the limit of detection of THC in blood in 0.3g/L.
Tinctures of cannabis were once common but were removed from pharmacopoeias many years ago. Currently, the two main cannabinoids from the cannabis plant that are of medical interest are THC and CBD. THC can increase appetite and reduce nausea. Cannabinoids are chemicals related to delta-9-tetrahydrocannabinol (THC), marijuana’s main mind-altering ingredient that is responsible for making people “high.” The marijuana plant contains more than 100 cannabinoids. Scientists, as well as illegal manufacturers, have produced many cannabinoids in the lab. Some of these cannabinoids are extremely powerful and have led to serious health effects when misused. THC may also decrease pain, inflammation and muscle control problems. Unlike THC, CBD is a cannabinoid that does not make people “high”. Therefore it may find useful applications in reducing pain and inflammation, controlling epileptic seizures, and possibly even treating mental illness and addictions.
References:
http://www.emcdda.europa.eu/publications/drug-profiles/cannabis
https://www.drugabuse.gov/publications/drugfacts/marijuana-medicine