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Drug Facts: Cannabis

AKA: MARIJUANA, HASH, POT, WEED, BLOW, BLACK, SHIT, DRAW, HERB, and countless other slang names. Names can refer to the drug generically (e.g. blow), specific forms of the drug (e.g. shatter), plant strains (e.g. skunk) or route of administration (e.g. spliff).

Source: Cannabis (the drug) comes from the plants Cannabis Sativa and Cannabis Indica, plants that grows wild in any warm or modestly warm conditions. Cross-breeding different 'landrace' strains of cannabis plant has led to the creation of hundreds of new strains with different ratios of active compounds, growing characteristics and appearances.

Historically, most UK cannabis was imported as resin (hash), from North Africa, the Middle East and Asia. Herbal cannabis was also imported, primarily from the Caribbean.

Now, most UK cannabis is produced in the UK or mainland Europe. Smaller amounts of resin, often low-quality is imported from North Africa. The Dark Web has made good quality resin more accessible again, along with numerous extracts and concentrates.

THC and CBD: 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, tended, processed and stored.

THC is the key psychoactive component. It is probably responsible much of the euphoria and hilarity associated with cannabis. However, it may also be responsible for some of the negative symptoms including anxiety, paranoia and panic.

CBD appears to reduce some of the negative effects of THC, reducing the extent of anxiety and panic in some people. There is much discussion as to whether CBD is psychoactive in its own right. Some people find that it provides relief from negative symptoms but doesn’t on its own cause significant, if any intoxication.

Appearance: Cannabis comes in two common forms and several less common ones. The most common are RESIN or HERBAL cannabis. Extracts, including oils, resin glands, Butane Hash Oil, and Rosin (amber, shatter, honey) are increasingly widely available.

RESIN: Traditionally the resin glands were collected from the female plant by rubbing the plant or drying the flowers and allowing the resin glands to fall through a fine mesh. The resulting powder was then compressed to form hard blocks, ranging in colour from black, dark brown, through to light brown. Size will vary as to the quantity being sold, from fractions of an ounce up to larger dealer quantities.  Cannabis resin may have a distinctive sweet, cloying smell. It may be soft and malleable, crumbly, or very hard.

Much 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 reputedly other psychoactive compounds such as ketamine.

As a result, many people avoid resin and seek herbal forms wherever possible. However, high quality resins are increasingly widely available via the Dark Web, resulting in a small renaissance amongst people who prefer milder resins to stronger herbal forms of cannabis.

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 more potent.

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

OIL: the term “cannabis oil” is now more complicated as it can refer to CBD Oil, THC oil or a mix of the two. It is the psychoactive component(s) of the plant, extracted from the solid matter using solvents, and sold in a variety of concentrations. The colour of oil can range from pale yellow to dark brown.

This should not be confused with “hemp oil” or “hemp seed oil,” which is used as a food supplement and cosmetic ingredient. Produced by crushing seeds it is not psychoactive and unregulated.

CONCENTRATES: Active drug can be extracted from plant through a number of mechanisms, including freezing, centrifuge, heat, solvent, and pressure processes. The end product (oil, amber, BHO, bubblehash, polm etc.) is generally very potent.

Cost Cannabis costs vary massively according to amount purchased, quality and form of drug, availability and who is selling it.

Small, low quality deals of herbal cannabis (small amounts of flower, bits of leaf) sold in dealer bags often sell for 10 for under a gram. Such massively over-priced low-quality product is often sold to young people and is hugely lucrative to sellers, making the off-cuts worth around 300 an ounce.

Buds of herbal cannabis can range from around 100-300+ an ounce. Product claimed to be organic, exotic cultivars, or in other respects artisanal can command high prices. Pure oil and extracts are still more expensive.

Strength and Purity: Discussions about “how strong is cannabis” can be confusing. It is important to look at different factors:

The RATIO of THC to CBD varies from product to product and strain to strain. Older forms of cannabis resin had lower overall levels of THC and lower, but significant levels of THC. A typical North African resin could have composition around 9%THC:3%CBD.

Stronger, crossbred herbal cannabis tends to have negligible levels of CBD, with a profile around 14%THC:0.1%CBD.

Potency: The potency of a drug is how much of the active material is present. Extracts (Polm, shatter, BHO) are higher potency and low-quality herbal material is obviously lower in potency. Buds of cannabis flowers tend to be around 16%; extracts can be far higher, from 70-100% depending on the processes involved.

Adulterants: 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.
Herbal material could also be sprayed with synthetic cannabinoids though there is little evidence that this routinely happens.

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 additives, 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.

Products sold as cannabis oils including CBD oils have been found to contain synthetic cannabinoids.

There are numerous rumours of cannabis being impregnated with LSD or crack cocaine but such apocryphal tales are not evidence based and make little financial or practical sense.

 Methods of Use: Cannabis is primarily either SMOKED, VAPOURIZED or taken ORALLY (eaten or drunk).

Smoking can be done in JOINTS, PIPES, or though paraphernalia such as HOT KNIVES, LUNGS or BUCKET BONGS.

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. This is the most damaging way of using cannabis, with strong evidence linking the smoking of cannabis with tobacco to lung damage and elevated risk of cancer.

Cannabis PIPES allow the smoking of cannabis without tobacco. More advanced pipes allow the smoke to cool before entering the lungs reducing the amount of plant oils inhaled.

Water pipes (bongs) allow smoke to pass through water, removing some of the toxins and carcinogens.

Vapourisers are increasingly popular. They have become less bulky and more efficient. They heat up the cannabis to the point where the active compounds can be inhaled. This reduces the lung damage associated with smoking cannabis. In the past these were mains powered but increasingly vapes are available both for liquid extracts and for vapeing dry herbs.

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

The sale of pre-made “edibles” is becoming more widespread. Sweets, chews and gummies with differing levels of THC and CBD became popular in America where licensed cannabis outlets became more widespread.

Similar products are now being sold in the UK. If they contain THC they are illegal to possess. They are not always as labelled and so could contain a different dose or different chemical to what is on the packaging. There have been hospitalisations and fatalities linked to consumption of illicitly produced edibles.

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 vary dramatically. Factors including user experience and expectation, the quality and quantity of drug taken, route of administration, use of other substances, state at time of use and setting can all impact on the how the person feels during 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 cancer. Cannabis when smoked on its own without tobacco can still cause lung damage and may also be carcinogenic but most of the evidence suggests it doesn’t cause lung cancer. However, the issue remains unclear.

Using cannabis regularly can cause short-term memory loss, and low mood and depression.

Many sources argue that cannabis is linked to the development of mental health problems, most notably "cannabis psychosis." It is also claimed that cannabis can trigger underlying mental health problems. These various arguments are hotly disputed by pro- and anti-cannabis lobbyists. However, there is evidence or a correlation between heavy use of strong cannabis amongst young people and an increased incidence of serious mental illness in later years.

While it is not PHYSICALLY addictive, people can and do become psychologically dependent, and find stopping use difficult. Withdrawal symptoms can include disrupted sleep, vivid dreams, anxiety, irritability and loss of appetite.

Harm Reduction:

To reduce lung damage measures could include:


To reduce risk of unpleasant effects due to excess use:

To manage symptoms of cannabis OD:

To reduce risk of triggering or worsening mental health problems:

         Ideally hold off using until late teens if you use at all. There’s evidence that using strong cannabis when the brain is still developing increases risk;

         If you do use, less often, less strong, and less in each session will be safer;

         If you think you may be struggling with your mental health, cannabis may help in the short term but is likely to worsen things in the longer term. So trying to manage unpleasant symptoms with cannabis risks making these symptoms worse.

         Keep a track of your mood; do you find your anxiety, low mood or other symptoms get worse after heavy cannabis use? If so it’s probably not helping.

         Keep a note if you have really unpleasant symptoms from cannabis use – severe paranoia, delusions, panic or being very altered.
If symptoms like this happen more often or last longer it could be a sign that you and strong cannabis don’t get on so well anymore and continuing use could result in persisting mental health problems.

Legal Status:  Cannabis resin and herbal cannabis were moved back to Class B in 2008. It had previously been moved to Class C in 2004 following advice from the ACMD.

Herbal Cannabis is always a Controlled Drug regardless of the CBD content. Some suppliers sell CBD-only weed, and sites claims it is legal in the UK. It isn’t and possession is a criminal offence.

The maximum penalty for possession of Class B drugs is 7 years. The maximum penalty for supply remains at 14 years. In reality possession of cannabis will rarely result in a custodial sentence.

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.

Most forms of cannabis are Schedule 1 meaning that it is illegal to produce, possess and supply without a Home Office license. Such licenses were previously only granted for research and then under a Home Office scheme to allow for treatment. This has now been expanded making it possible for specialist Doctors to prescribe cannabis  for medical purposes.

CBD is not covered by the MoDA and where CBD is not in plant or resin form it is legal to possess provided it has no detectable THC in it.

Where CBD products are sold without claims to medical efficacy, they fall outside the Medicines legislation as well so CBD products are routinely sold as “food supplements.” Advocates of CBD say it may help a range of ailments including management of anxiety, pain, inflammation, sleep and other physical or mental health issues. Foods containing CBD are meant to seek Novel Food Authorisation under the Food Standards Agency but not all do or have done so.

CBD is widely considered not to be psychoactive (though this is contested), and so supply is not covered by the Psychoactive Substances Act.

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. Driving under the influence of cannabis is illegal.

Internationally the legal status of Cannabis is rapidly changing. Variously, countries have depenalised it, made it available for medical use, decriminalized it or, as in the case of Canada, made it fully legal for recreational use.

Cannabis as medicine UK: There is growing and belated international recognition as to the medicinal benefits of cannabis.

The UK has slowly started to change the legilsation to make Cannabis more accessible but it is still a restictive and expensive situation.

The first whole-cannabis derived medicine to be licensed in the UK was Sativex, an oral spray with a 50:50 THC:CBD ratio. It was made a Class B, Schedule 4i drug in 2013.

CBD-related products are available without prescription and without medical assessment. However, there is a lack of reputable information about doses, interactions and utility. Not everyone derives benefit from CBD-only treatments and may write off “cannabis as medicine” when THC and CBD may have been more useful.

CBD only medicine in the form of Epidyolex is now prescribed in the UK but its use is limited to childhood epilepsy.

Following widespread coverage in the media of children with epilepsy seeking treatment with cannabinoids, the Home Office made further changes to the regulations, creating a new family of “cannabis-based products for medicinal use in humans.” These fall under Schedule 2 of the Misuse of Drugs regulations.

This does not mean that Doctors can now prescribe cannabis. Only clinicians listed on the Specialist Register of the General Medical Council can prescribe cannabis-based products and they must adhere to the regulations from the MHRA relating to unlicensed “specials.”

Such provision is now increasingly available through private clinics which may charge for an initial consultation, follow-ups, repeat prescriptions and the cost of the cannabis itself.

For most people the costs are the same or greater than buying street drugs. The benefits – a legal, labelled product of known strength – is only available to people who can afford it.

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

Trends in Use: Cannabis use had been declining since 1998 but use has been increasing since 2012/13.

While levels of use are not back to the previously high levels the increase is significant and sustained.



Testing: Cannabis urine tests are looking for THC metabolites. These are detectable in urine for as long as thirty days, far longer than most other drugs. A person who is exclusively using good-quality CBD or Hemp Oil should not test positive for THC. A positive test result could be as a result of CBD products with a level of THC above the legal limits, Hemp Oil made with hemp seeds that have not been adequately cleaned or use of other cannabis products. A positive test result could result from passive inhalation especially if sustained exposure took place in a confined environment.

This is a shorter briefing. A full cannabis resource pack is available on the KFx Website here: http://www.kfx.org.uk/resources/Cannabis%20Distribution%20Pack%20v.4.pdf

There is a toolkit for working with cannabis dependency here: http://www.kfx.org.uk/resources/cannast2015.pdf

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