A Closer Look at Mental Health · Booklet 35

Cannabis Use Disorder

"Natural" does not mean harmless.

Cannabis use disorder describes the point at which products containing THC, derived from the cannabis plant, turn into a pattern of dependence, with signs such as loss of control, intense craving, loss of functioning, withdrawal, and continued use despite harm.

Read this booklet not as a checklist of labels, but as a calm guide to help you make sense of your experience. Noticing symptoms does not on its own mean a diagnosis. What matters is duration, intensity, functioning, and the distress being experienced.

This booklet addresses common misconceptions about cannabis and its clinical risks in plain language.

What cannabis is and why it matters

Cannabis is a psychoactive substance derived from the cannabis plant that can be consumed in different ways. The component most discussed for its effects is THC. THC can affect perception, mood, attention, the sense of time, the reward system, and in some people anxiety or paranoia.

The fact that cannabis comes from a plant does not automatically make it safe. Tobacco is also a plant, and some poisons are natural. The clinical question is not whether a substance is natural, but what effects it creates on the brain, body, relationships, and life.

Criteria for dependence

Cannabis use disorder is understood through criteria similar to those used for other substance use disorders. Important signs include using more than intended, failing attempts to cut down, spending a great deal of time using or recovering, intense craving, neglecting responsibilities, and continuing despite social problems.

Tolerance can develop. More use may be needed to achieve the same effect. Withdrawal symptoms can also appear. Restlessness, sleep problems, changes in appetite, headaches, irritability, and physical discomfort can make the period of stopping more difficult.

Early age of first use, frequent use, high THC content, predisposition to psychosis, family history, and accompanying psychological difficulties can all increase the risk.

Short and long term risks

In the short term a person may experience relaxation, altered perception, distortion of the sense of time, or pleasure. However some people experience panic attacks, intense anxiety, feelings of unreality, paranoia, and loss of control. The effect can vary depending on the person's expectations, mood, amount used, setting, and predisposition.

One of the most significant risks associated with cannabis use is its relationship to psychosis. Particularly in people with a predisposition, the risk of psychotic symptoms can increase with frequent use that begins at an early age and involves high THC content. With chronic use, loss of motivation, drifting away from educational and work goals, narrowing of relationships, and decline in cognitive performance can also occur.

The risk of normalisation

The fact that a behaviour becomes widespread does not mean it is safe. Cannabis gaining different legal statuses in some countries does not eliminate its clinical risks.

Treatment and environmental organisation

The first goal in treatment is for the person to understand their cycle of use. When do they use? Which feeling are they regulating through use? Which social circle, place, music, night-time routine, or sense of emptiness triggers use? These questions make environmental organisation visible during the process of stopping.

Cognitive behavioural therapy, motivational interviewing, relapse prevention, building alternative sources of reward, and addressing accompanying anxiety, depression, or psychotic symptoms are the core approaches. Physical withdrawal is generally not as dangerous as with alcohol, but psychological distress and the risk of relapse can be pronounced.

If there are psychotic symptoms, intense paranoia, thoughts of self-harm, or severe loss of functioning, psychiatric evaluation should not be delayed.

A brief closing note

Cannabis use disorder often grows in the shadow of the phrase "I can stop whenever I want." Yet once loss of control has begun, the matter is no longer one of knowledge, but of structured support, environmental organisation, and building alternative life resources.

Questions to ask yourself

  1. Which feeling or situation am I using cannabis to escape?
  2. How do I feel on days when I do not use?
  3. How does my use affect my education, work, relationships, or motivation?
  4. Does my risk of relapse increase when I return to the environment where I used?

Source note

This booklet is an original psychoeducational text. Its clinical frame is kept consistent with the sources below.

  • NIDA. Cannabis (Marijuana). 2024.
  • CDC. Cannabis Health Effects.
  • NICE CG51. Drug misuse in over 16s: psychosocial interventions. 2007.

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