Cannabis

Cannabis means the plants in the cannabaceae family. The cannabis plant contains hundreds of chemical substances, including over 100 cannabinoids and aromatic terpenes and flavonoids.

The effects of cannabis are caused by the actions of its cannabinoids on biological 'targets', i.e. a system of specific receptors and molecules found throughout the human body, known as the endocannabinoid system. Most scientific research has focussed on two cannabinoids in particular. Delta-9-tetrahydrocannabinol, commonly known as THC, is the main psychoactive ingredient. When THC is consumed, it acts on the brain's endogenous cannabis receptors. The effects of THC have been found to be associated with a dose-response relationship, with heavy consumption being more strongly associated with negative impacts on health and social conditions. The second cannabinoid that has attracted much scientific research is cannabidiol (CBD). In Luxembourg, the cannabis that is available on the illegal market comes mainly in two forms:

• flowering tops;
• 'hashish', which is produced from cannabis plant resin.

Although cannabis is a natural substance, it is not harmless. Cannabis consumption poses several health risks. For more information on the risks associated with cannabis consumption, please click here.

Cannabis contains more than 500 different substances, including:

• tetrahydrocannabinol (THC);
• cannabidiol (CBD).

The cannabis plant contains hundreds of chemical substances, including over 100 cannabinoids and aromatic terpenes and flavonoids. Most scientific research has focussed on two cannabinoids in particular, namely: tetrahydrocannabinol (THC) and cannabidiol (CBD).

THC is the main active ingredient and, among other effects, has a disrupting (psychoactive) effect in people who consume cannabis. THC, which is found in dried cannabis flowering tops, is not naturally psychoactive; it has to be decarboxylated – for example by heating – to make it psychoactive.

The higher a product's THC concentration, the stronger its psychoactive effects and the greater the risks to health. The average concentration of THC in cannabis has increased steadily in recent decades, from 7 % in 2006 to 20 % in 2021.

The cannabis plant contains hundreds of chemical substances, including over 100 cannabinoids and aromatic terpenes and flavonoids. Most scientific research has focussed on two cannabinoids in particular. tetrahydrocannabinol (THC) and cannabidiol (CBD).

CBD is a substance that is also found in cannabis, but it does not have the disruptive properties characteristic of THC. CBD has sparked significant interest among researchers in recent years because of its potential therapeutic properties.

Compared to THC, the average CBD concentration in cannabis has decreased steadily since the early 2000s, creating an imbalance between the THC and CBD concentrations in cannabis.

Knowledge of cannabis and its impacts is constantly evolving. Most people who consume cannabis do not suffer the negative consequences of its use. However, various factors seem to favour their appearance in some people.

Regardless of how cannabis is consumed, it poses health risks. The only way to avoid any risks is abstinence. If you choose to consume cannabis, reduce the risks to your health by considering and taking on board the factors and information below:

Risk factors

As mentioned above, consuming cannabis, in any form, poses risks.

If you consume cannabis, the potential risks associated with it are higher if the cannabis:

• Comes from an unknown source and there is no quality control or product labelling (THC and CBD concentrations, presence of impurities and contaminations, cutting agents, etc.);
• Has high THC concentrations and low CBD concentrations;
• Is consumed in high-risk ways (e.g. by smoking it with tobacco);
• Is consumed at a young age;
• Is consumed very frequently and intensely, particularly in the case of cannabis with high THC concentrations and low CBD concentrations.

In particular, there is a risk of addiction, i.e. abuse and/or dependency, especially in the case of prolonged consumption at high and frequent doses.

Attention should therefore be paid to possible signs such as decreased motivation, restlessness when going without, a depressive state, social withdrawal, etc.

Do you still have questions about cannabis and its risks? We recommend calling the National Centre for Prevention of Addictions (Centre national de prévention des addictions - CNAPA) hotline on + 352 49 77 77 55. The CNAPA works to prevent addictions and promote health by providing information, raising awareness, organising training courses, and facilitating coordination.

The following groups of people are particularly exposed to risks in the event of cannabis consumption, and cannabis consumption is not recommended for them:

• Pregnant and/or breastfeeding women;
• Children, adolescents and young adults under the age of 25: cannabis can have harmful effects on various aspects of mental, neuronal and emotional development, depending on the age at which cannabis consumption started, and the duration and intensity of consumption;
• Patients with a history of addiction and/or consumption of substances such as alcohol, drugs or other medicinal products;
• Patients with a history of mental illness (personal or within the family);
• Patients with kidney or liver failure;
• Patients with a pre-existing heart condition;
• Elderly or bedridden people, or people with reduced mobility.

As a reminder, cannabis consumption is not recommended for these groups of people.

Do you still have questions about cannabis and its risks? We recommend calling the CNAPA hotline on + 352 49 77 77 55. The CNAPA works to prevent addictions and promote health by providing information, raising awareness, organising training courses, and facilitating coordination.

Adverse effects

The adverse effects of cannabis, especially cannabis with high THC concentrations, vary greatly from one person to another. Problems of the central nervous system, such as dizziness, vertigo, memory and attention problems, psychiatric problems, especially mood disorders, signs of depression and, in some cases, hallucinations or psychotic episodes; dietary or gastro-intestinal problems, and cardiovascular problems, such as palpitations or faster heart rate, have been reported.

Additive effects and interaction with medicinal products

Some adverse effects of cannabis can be exacerbated in the presence of other medicinal products that have neurological effects (also known as central effects), such as: benzodiazepines, barbiturates, opioids, antihistamines, muscle relaxants and epilepsy medicines. Similarly, it is strongly recommended not to consume alcohol in combination with cannabis, or smoke it with tobacco, as these two modes of consumption are high-risk modes of consumption.

It is worth noting that, at present, little scientific data has been published. As such, all of the possible interactions between cannabis and other substances are not yet known.

Effects on drivers

Cannabis consumption, especially cannabis with high THC concentrations, can have significant effects on the central nervous system, such as dizziness and/or drowsiness. Indeed, judgment and the performance of tasks that call for skill can be impaired.

According to the Law of 14 February 1955 (as amended) regulating traffic on all public thoroughfares, 'the penalties provided for in paragraph 1 shall apply to any driver of a vehicle or an animal, as well as any pedestrian involved in an accident, whose body is found to contain one of the following substances: THC […] with a serum level greater than or equal to 1 ng/mL […]'.

In practice, the legal threshold equates to zero tolerance for persons driving a vehicles under the influence of cannabis.

Do you still have questions about cannabis and its risks? We recommend calling the CNAPA hotline on + 352 49 77 77 55. The CNAPA works to prevent addictions and promote health by providing information, raising awareness, organising training courses, and facilitating coordination.

Permission to grow cannabis at home, and the decriminalisation of small quantities of cannabis in public places, are one of the first steps in the implementation of the pilot scheme for legal access to cannabis for non-medical purposes.

By opting to regulate home-grown cannabis, the Government hopes to control consumption and reduce the associated risks and harm. This decision is part of an approach to public health that reflects a political commitment to strike a balance between prevention, risk reduction and tackling crime.

Read the section on home-grown cannabis in the citizen space.

Restocking of THC-dominant flowering tops will end on 01/01/2025. This product will be available while stocks last.

It is recommended that you contact your prescribing doctor, who will discuss with you whether continuing your medicinal cannabis treatment with cannabis oil extracts is feasible, depending on your pathology and other available therapeutic options.

No. As with any change in treatment, you should discuss with the patient whether oil extracts are the best therapeutic option, depending on the pathology to be treated and available treatments.

There is no established direct equivalence. A therapeutic titration may be necessary, on a case-by-case basis, to achieve the minimum tolerated effective dose by gradually increasing the oil extract doses.

It is important to remind patients that:

• cannabis oil extracts should not be vaped/smoked!
• the perceived effect of cannabis oil extracts is not the same as that of flowering tops (no flash effect), as the pharmacokinetics are different – flowering tops act quickly but not for long, while oil extracts work slowly but over a long time.

(Bhaskar, A., Bell, A., Boivin, M. et al. Consensus recommendations on dosing and administration of medical cannabis to treat chronic pain: results of a modified Delphi process. J Cannabis Res 3, 22 (2021))

In the case of addiction, stopping cannabis consumption can cause symptoms such as irritability or aggressiveness, anxiety, sadness, mood swings or depression, agitation, problems sleeping, sleeping too much, loss of appetite and weight loss, sweating or nausea, and milder symptoms such as tiredness, weakness, yawning and psychomotor retardation.

According to the literature, withdrawal can affect up to 47 % of cannabis users. The factors associated with higher cannabis withdrawal syndrome were the clinical environments (in particular hospital or outpatient care, as opposed to population settings), concurrent use of tobacco or other substances, and daily cannabis use.

Gradual withdrawal is recommended over a period of four to eight weeks (depending on the patient, the therapeutic indication, the frequency of use and the concentration of the product).

How long withdrawal lasts is highly individual, and depends on the frequency and duration of use, and on the concentration of the product used. After quitting, flushing the system of the cannabinoids accumulated in adipose tissue can take up to 12 weeks.

There are various associations that you can turn to for information or assistance. We recommend viewing the following websites:

• National Centre for the Prevention of Addictions (CNAPA)
• Centre thérapeutique Useldange (CTU)

Useful addresses can be found on the website of the Rehaklinik du Centre hospitalier neuro-psychiatrique (CHNP)