The Risks and Difficulties with Cannabis Use.

Cannabis is arguably the most widely used illicit drug in the UK. For many people it is experienced as relaxing or social, and for some it plays a role in self-medication. Yet use is not risk-free. Over the last decade the cannabis market has changed, with higher average THC potency, novel products, and shifting patterns of use. Growing evidence shows that cannabis can cause or worsen mental and physical health problems, impair cognition, and place strain on relationships, work and wellbeing. Understanding those risks helps people make informed choices and, where necessary, get the right help.

This article summarises the main health and social harms associated with cannabis use, highlights who is most at risk, explains why treatment can be challenging, and describes how Cheshire Sobriety Clinic supports people using a combined approach of Rapid Transformational Therapy® (RTT®) and talking therapy.

How cannabis affects the brain and body

Cannabis contains several active compounds, chiefly delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC produces intoxicating effects by acting on the endocannabinoid system and increasing dopaminergic activity in reward pathways, which can produce euphoria but also anxiety, paranoia and altered perception (StatPearls, 2024). Repeated exposure alters neural circuits involved in motivation, memory and impulse control and, depending on age of first use and frequency, can produce measurable changes in brain function (Gowin et al., 2025; Karlsgodt et al., 2023).

Importantly, the strength of cannabis products has increased in recent years. Large surveillance studies show that average THC concentrations have risen markedly in many markets, a change associated with higher risk of acute adverse effects and long-term harms (ElSohly et al., 2024; Di Forti et al., 2019).

Key health risks

1. Increased risk of psychosis and severe mental illness

One of the most robust findings in cannabis research is the association between frequent use of high-potency cannabis and an elevated risk of psychotic disorders. Epidemiological and case-control studies indicate that daily use of high-THC products can multiply the risk of a first episode of psychosis compared with non-use (Di Forti et al., 2019). This is not simply a small effect: population attributable fractions calculated in multi-site studies suggest that eliminating high-potency cannabis in some settings could prevent a meaningful proportion of new psychosis cases (Di Forti et al., 2019).

2. Cognitive impairment and developmental risks in young people

Adolescence and young adulthood are critical windows for brain development. Studies show that early and frequent cannabis use is linked to poorer outcomes on memory, attention, and executive function. Neuroimaging and cognitive research indicate that heavy use during adolescence can change neural structure and function in ways that persist into adulthood, reducing school performance and increasing risk of later dependence (Karlsgodt et al., 2023; Gowin et al., 2025).

3. Cannabis use disorder and dependence

A substantial minority of people who use cannabis develop cannabis use disorder (CUD). Estimates vary by method and population, but authoritative public health sources report that around 1 in 10 adult users develop dependence, rising to about 1 in 6 for those who start in adolescence or use frequently (SAMHSA/CDC summaries; StatPearls, 2024). Dependence involves tolerance, withdrawal (sleep disturbance, irritability, low mood), and continued use despite harm, all of which complicate quitting.

4. Anxiety, depression and suicidal thoughts

Cannabis is associated with an increased risk of mood problems in some users. While the relationship is complex and bidirectional, longitudinal studies and clinical reviews evidence links between frequent cannabis use and higher rates of depression, anxiety and self-harm for some individuals, particularly those with early onset use, heavy use or pre-existing vulnerability (Gowin et al., 2025; Karlsgodt et al., 2023).

5. Acute harms: accidents and intoxication

Intoxication with cannabis impairs coordination, reaction time and judgement, increasing the risk of road traffic collisions and workplace accidents (ONS, 2024). High-THC products are more likely to induce acute anxiety, panic attacks, and transient psychotic symptoms. Emergency department presentations for severe intoxication, especially when cannabis is mixed with other substances, have risen in some settings (ElSohly et al., 2024).

6. Respiratory and other physical effects

Smoking cannabis is associated with respiratory symptoms such as chronic bronchitis and cough. While the causal link between cannabis smoking and lung cancer is less clear than for tobacco, habitual smoking increases airway inflammation and may contribute to long-term respiratory problems. Newer consumption methods (vaping, edible concentrates) carry distinct risks, including unpredictable dosing and contamination (ElSohly et al., 2024).

Who is most at risk?

The risks of cannabis vary by age, pattern of use, product potency and individual vulnerability.

• Adolescents and young adults are at the highest risk of long-term cognitive and psychiatric harms because their brains are still developing (Karlsgodt et al., 2023).

• Daily or near-daily users face much higher risks of dependence, cognitive deficits and mental-health problems compared with occasional users (Di Forti et al., 2019).

• Users of high-potency cannabis (often called “skunk” in the UK) show greater likelihood of psychosis and acute adverse effects than users of lower-potency resin or mixed products (Di Forti et al., 2019; ElSohly et al., 2024).

• People with family history or prior mental illness may be more sensitive to cannabis-induced worsening of psychiatric symptoms (Gowin et al., 2025).

  
  

Why quitting or reducing cannabis can be hard

Treatment and recovery for problematic cannabis use are challenging for several reasons.

First, cannabis withdrawal is real and may include sleep disturbance, irritability, reduced appetite, low mood and strong cravings, which often precipitate relapse (StatPearls, 2024). Second, there is currently no widely accepted, licensed medication with strong evidence for treating CUD; psychosocial and behavioural therapies are the principal effective interventions (Gates et al., 2016; Winters, 2021). Third, social and environmental factors, peer networks, stressors and availability often maintain use. Finally, cognitive impairment associated with heavy use can make engaging with structured therapy harder.

What works: evidence for treatment

A consistent conclusion across systematic reviews is that psychosocial interventions reduce cannabis use more than no treatment. Cognitive behavioural therapy (CBT), motivational enhancement therapy (MET) and contingency management show the best evidence, often in combination (Gates et al., 2016; Sabioni et al., 2019). Recent syntheses emphasise multi-component programmes, tailoring to individual need, and addressing co-occurring mental health problems simultaneously (Connor et al., 2024; Winters, 2021). Early intervention for youth, family involvement and flexible delivery (including online options) improve reach and outcomes.

UK context and current data

National data show cannabis remains the most commonly used illegal drug in England and Wales. The Office for National Statistics reports that a substantial proportion of users use more than once a month, and daily use has persisted among a minority of users (ONS, 2024). Government treatment datasets also indicate that cannabis accounts for a significant share of adults in community drug treatment services, often alongside other substances such as opioids (OHID, 2024). In parallel, academic and public-health surveillance highlight rising availability of high-potency cannabis and associated increases in psychiatric presentations in some urban centres (Di Forti et al., 2019; ElSohly et al., 2024).

How Cheshire Sobriety Clinic can help: RTT® plus talking therapy

Because cannabis problems are typically multi-faceted, Cheshire Sobriety Clinic takes an integrated approach that combines Rapid Transformational Therapy® (RTT®) with evidence-based talking therapies.

1. Comprehensive assessment We begin by assessing cannabis use history, patterns, product types, co-occurring mental health issues, social circumstances and physical health. This ensures treatment is personalised.

   
   

2. Rapid Transformational Therapy (RTT®) RTT® works at the subconscious level to identify and reframe deep-seated beliefs and emotional drivers that often sustain substance use. For many clients, RTT® reduces the emotional intensity of triggers and addresses shame, low self-worth or anxiety that contributed to problematic use.

   
   

3. Talking therapies: CBT and motivational approaches CBT and motivational interviewing form the core of the talking-therapy element. These therapies teach practical skills to manage cravings, restructure unhelpful thoughts, manage stress, and plan for high-risk situations. They are the interventions most consistently supported by systematic reviews for reducing cannabis use (Gates et al., 2016; Sabioni et al., 2019).

   
   

4. Treating co-occurring problems together Because cannabis use often co-exists with depression, anxiety or psychosis vulnerability, we integrate mental-health care into the same treatment plan rather than postponing one until the other is “fixed.” This integrated approach aligns with best practice recommendations.

   
   

5. Relapse prevention and social support Recovery involves rebuilding daily life. Cheshire Sobriety Clinic helps clients improve sleep, routine, relationships and work plans while linking them with community supports and medical services where needed.

   
   

6. Flexible delivery and follow-up We offer in-person and online sessions to fit around life commitments and provide ongoing follow-up to manage setbacks, which are a normal part of recovery.

   
   

Final thoughts

Cannabis is not risk-free. For many people occasional use may pose little lasting harm, but for others, especially young people, daily users and those using high-potency products, cannabis can cause significant mental, cognitive and social harms. The best way to reduce risk is to avoid early onset use, limit frequency, choose lower potency products if using, avoid mixing with other substances and seek help early if use becomes problematic.

If cannabis is affecting your mood, thoughts, memory, relationships or daily functioning, Cheshire Sobriety Clinic can help. Our combined RTT® and talking-therapy approach addresses both the conscious and subconscious drivers of use, supports practical behaviour change, and links you with medical and social supports so you can regain control and rebuild quality of life.

References

Di Forti, M., Marconi, A., Carra, E., Fraietta, S., Trotta, A., Bonomo, M., ... & Murray, R. M. (2019) ‘The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): a multicentre case-control study’, Lancet Psychiatry, 6(5), pp. 427–436.

ElSohly, M. A., et al. (2024) ‘A 10-year trend in cannabis potency (2013–2022) in different regions’, Frontiers in Psychiatry / Cannabis Research (journal), 2024.

Gates, P. J., Trinh, L., & Mitchell, A. (2016) ‘Psychosocial interventions for cannabis use disorder’, Cochrane Database of Systematic Reviews, CD005336.

Gowin, J. L., et al. (2025) ‘Brain function outcomes of recent and lifetime cannabis use: findings from JAMA Network Open’, JAMA Network Open, 2025.

Karlsgodt, K. H., et al. (2023) ‘Cannabis use in adolescence: vulnerability to cognitive and neural changes’, Neuroscience & Biobehavioral Reviews, 2023.

NHS England (2024) ‘Cocaine and crack cocaine: information and advice’ (for general drug harms and service advice). Available at: https://www.nhs.uk (Accessed: 2025).

Office for Health Improvement and Disparities (OHID) (2024) ‘Adult substance misuse treatment statistics 2023 to 2024: Report’. GOV.UK.

Office for National Statistics (ONS) (2024) ‘Drug misuse in England and Wales: year ending March 2024’.

Sabioni, P., et al. (2019) ‘Psychosocial and pharmacological interventions for cannabis use disorder: A review’, Focus (American Psychiatric Publishing), 17(2).

StatPearls (Patel, J.) (2024) ‘Cannabis Use Disorder’, StatPearls [Internet], Treasure Island (FL): StatPearls Publishing.

Winters, K. C. (2021) ‘Interventions for cannabis use disorder: A review’, Current Opinion in Psychology, 2021.

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