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Drug Facts :: Cannabis

AKA: MARIJUANA, HASH, POT, WEED, BLOW, BLACK, SHIT, DRAW, HERB, and at least 100 other different slang names. Increasingly common are cultivated strains such as SKUNK and SUPER SKUNK.

SOURCE: Cannabis primarily comes from the plant Cannabis Sativa, a plant that grows wild in any warm or modestly warm conditions. By cross-breeding between different 'landrace' strains of cannabis plant, a large number of hybrid strains have been created with different ratios of active compounds, growing characteristics and appearances.

Historically, UK cannabis was primarily imported, mostly in the form of resins, especially from North Africa the Middle East and Asia. A smaller amount of herbal cannabis was imported, primarily from the Carribean.

Increasingly, UK cannabis is the result of cultivation within the UK or mainland Europe. Smaller amounts of resin, mostly low-quality are imported from North Africa.

Cannabis contains a number of psychoactive compounds, the most significant of which are THC (tetrahydrocannabinol) and CBD (cannabidiol). The amount of THC and CBD in a plant is partly determined by its genetics, but also about how it is grown and tended.

The amount of active drugs in the end product will be further influenced by how the plant is processed and stored.

APPEARANCE: Cannabis comes in two common and one more rare form. The commonest forms are RESIN or HERBAL. Less common is OIL.

RESIN: Cannabis plants, especially the flowers, contain and exude resin which, when collected and compressed, forms hard blocks. These may range in colour from black, dark brown, through to light brown. Size will vary as to the quantity being sold, e.g from a block over a foot long, weighing a kilo, down to small lumps measuring a few centimetres. Cannabis resin may have a distinctive sweet, cloying smell. It may be soft and malleable, crumbly, or very hard.

Unfortunately, most of the resin sold in the UK as "soap-bar" is a low-quality product, extracted from plant material using solvents and often adulterated with binding and bulking agents and with other psychoactive compounds such as ketamine.

HERBAL: Herbal cannabis is composed of either small dried leaves, dried flowering heads, or a mixture of the two. Dried leaves look much like dried herbs. Flowering parts are often either light green, yellowish or purple, and may be dusted with white crystals. Theoretically these should be THC but in practice may be an adulterant added to make the plant look "crystally" and therefore potent.

"WEED" or "HERB" usually refers to leafy matter only, while "BUSH" or "SENSIMELIA" refers to flowering parts. Sensimellia refers to a female plant that has not been polinated, and so has no seeds in it. Most UK-grown cannabis will be grown like this.

OIL: much less common in this country, pure cannabis oil is very strong and contains no solid matter. It usually comes in small vials, and is light brown, golden colour.

COSTS: Cannabis pricing has been relatively stable for a long time, though does experience wild fluctuations at times of shortage ("droughts.") Cannabis pricing is usually by weight, though small amounts may be sold in £5 or £10 deals. Often sold by imperial measures, weights are based on ounces, and divisions of an ounce. Typically, an ounce of resin sells for between £80 and £120, often dependent on quality. After this, prices become relatively higher; half-ounces are usually around £50, quarters are around £30, eighths are around £20, and the smallest amount sold are £12-15. Herbal cannabis, and, from time-to-time, resin, are sold by the gramme. Prices are broadly equivalent, at a rate of roughly 28 grammes to the ounce. Good quality strains are more expensive.

QUALITY: Two main factors are of concern. THC is one of the active chemicals in cannabis, and the more of this that is present, the stronger the cannabis. Some strains and batches of cannabis can be very strong whilst in others, the THC content is negligible. The heavily cultivated strains such as Skunk can be very high in THC.

The other major concerns are products that have been cut, and contain little or no cannabis at all. Dried leaves, mixed herbs or any other leafy produce may be passed off as herbal cannabis. Mixtures of wax, henna, plastic or liquorice have been passed off as cannabis resin. However, most people buy off people they know rather than dealers on the street, so these risks are reduced.

The low grade "soap-bar" resin sold in the UK is almost invariably low quality and contains potentially dangerous additived, including plastic and paraffin wax.

Herbal cannabis buds have also been contaminated, increasingly with small glass beads that have been sprayed on to the buds. There has been concern that inhalation of these beads can cause respiratory problems.

METHODS OF USE: Cannabis is primarily either SMOKED or taken ORALLY (eaten or drunk). Smoking can be done in JOINTS, PIPES, or though paraphernalia such as HOT KNIVES or BOTTLES. Cannabis in joints is often smoked with tobacco, though herbal cannabis can be smoked on its own. The cannabis is placed in cigarette papers, and, if used, tobacco is added. A cardboard cylinder ("a roach") is added, and the prepared joint is smoked.

Some people prefer to use small PIPES, in which a small amount of cannabis resin or herbal cannabis is placed and smoked. Alternatively water pipes (bongs) may be used. Here, the smoke passes through water, removing some of the toxins and carcinogens.

Other methods such as hot-knives or using bottles are less widespread, and tend to be more wasteful. For example, with hot-knives, a small pellet of resin is placed between two kitchen knives which have been heated up, and the vapour inhaled.

A high-tech method of smoking cannabis is a vapouriser, which heats up the cannabis to the point where the active compounds can be inhaled. This is reputed to be a less hazardrous way of smoking cannabis.

Cannabis can be mixed into food or mixed into drinks. It may be made into cakes ("hash cakes") or tea-like drinks.

When smoked, the effects of cannabis take effect within a few minutes. Absorption though the stomach is slower and can take up to an hour. The effects of eating cannabis can last several hours, while they tend to wear off within an hour when smoked.

EFFECTS: The effects of cannabis are not always very clearly defined. Some users report little or no effects, and others experience very intense effects. Certainly, the effects of cannabis use are often dependent on the experience and expectations of the user, and the setting and mood at the time of use. The following symptoms are most frequently recorded at moderate dosages; some may or may not be present:

Relaxation, tiredness, light-headedness, hilarity, excitability, nausea, euphoria, anxiety, redness of the eyes, enhanced appreciation of sound and colour, increased appetite, paranoia.

Unwanted side effects such as nausea, palpitations and anxiety are sometimes made worse by alcohol.

HEALTH IMPLICATIONS: Smoking cannabis, especially with tobacco, carries health risks. These relate to lung damage, especially bronchial problems, and an increased risk of lung and throat cancers. These problems are not removed by smoking without tobacco, and some studies indicated that cannabis smoke is more carcinogenic than tobacco. Certainly, people smoking cannabis tend to hold the smoke in their lungs longer, and this means more damage can occur.

Using cannabis regularly can cause short-term memory loss, and apathy or listlessness. While it is not PHYSICALLY addictive, people can and do become psychologically dependent, and find stopping smoking difficult.

Many sources argue that cannabis is linked to the development of mental health problems, most notably "cannabis psychosis." It is also claimed that cannabis and trigger underlying mental health problems. These various arguments are hotly disputed by pro and anti cannabis lobbyists. However, there is increasing evidence that the heavy use of strong cannabis amongst young people increases the risk of serious mental illness.

LEGAL STATUS: Cannabis was reclassified back to Class B in 2008. This effectively meant that the maximum penalty for possession went back up to a maximum of seven years. The maximum penalty for supply remains at 14 years. Cannabis is a Schedule 1 drug meaning that it is illegal to produce, possess and supply without a Home Office licence. Such licenses are only granted for research purposes. While possession of seeds is not illegal, the cultivation of plants is. Allowing premises to be used for the consumption of cannabis is an offence.

Possession of cannabis is an arrestable offence though most people over the age of 18 will get a "cannabis warning" for their first cannabis offences. For a second offence, adults are likely to be offered a PND (Penalty Notice for Disorder) which will result in a fine but not a Criminal Record. Subsequent offences will result in police charges and a criminal record.

For more information on changes to cannabis policing, please consult separate KFx briefing.

OTHER INFORMATION: Cannabis is the most widely used illegal drug, and is popular across age, class, gender and race. It is widely available.

Cannabis metabolites can detectable in urine for as long as thirty days, far longer than most other drugs.

In the Netherlands, cannabis has NOT been legalised, but has been decriminalised, and is openly sold in coffee-shops.

Much attention has been paid, of late, to the perceived health benefits attached to cannabis use. It has been indicated for a wide range of illnesses and diseases. In 2010 the medicine Sativex received its licence allowing it to be used as a medicine in the UK. It is an extract from hybridised cannabis plants, and has a ratio of THC to CBD of almost 1:1 making it very different in composition to recreational strains of cannabis.

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