Internet Mental Health

Prediction: Episodic/Chronic For Years

  • Impaired cognitive functioning (apathy, memory loss, learning impairment)
  • Irrationality (delusions, hallucinations) triggers schizophrenia in 4%-7% of users
  • Detachment (suspiciousness, social withdrawal)
  • Marital/child neglect in heavy users; legal problems
  • Denial of addiction; respiratory illness; lung cancer


Dependence Syndrome Due To Use Of Cannabinoids F12 - ICD10 Description, World Health Organization
Repeated use of cannabinoids that typically includes a strong desire to take the drug, difficulties in controlling its use, persisting in its use despite harmful consequences, a higher priority given to drug use than to other activities and obligations, increased tolerance, and sometimes a physical withdrawal state.
Cannabis Use Disorder - Diagnostic Criteria, American Psychiatric Association

An individual diagnosed with cannabis use disorder needs to meet all of the following criteria:

  • A problematic pattern of cannabis use leading to clinically significant impairment or distress, as manifested by at least two of the following, occurring within a 12-month period:

    • Cannabis is often taken in larger amounts or over a longer period than was intended.

    • There is a persistent desire or unsuccessful efforts to cut down or control cannabis use.

    • A great deal of time is spent in activities necessary to obtain cannabis, use cannabis, or recover from its effects.

    • Craving, or a strong desire or urge to use cannabis.

    • Recurrent cannabis use resulting in a failure to fulfill major role obligations at work, school, or home.

    • Continued cannabis use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of cannabis.

    • Important social, occupational, or recreational activities are given up or reduced because of cannabis use.

    • Recurrent cannabis use in situations in which it is physically hazardous.

    • Cannabis use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by cannabis.

    • Tolerance, as defined by either of the following:

      • A need for markedly increased amounts of cannabis to achieve intoxication or desired effect.

      • A markedly diminished effect with continued use of the same amount of cannabis.

    • Withdrawal, as manifested by either of the following:

      • The characteristic withdrawal syndrome for cannabis:

        • Cessation of cannabis use that has been heavy and prolonged (i.e., usually daily or almost daily use over a period of a least a few months).

        • Three (or more) of the following signs and symptoms develop within approximately 1 week after the cessation of heavy cannabis use:

          • Irritability, anger, or aggression.

          • Nervousness or anxiety.

          • Sleep difficulty (e.g., insomnia, disturbing dreams).

          • Decreased appetite or weight loss.

          • Restlessness.

          • Depressed mood.

          • At least one of the following physical symptoms causing significant discomfort: abdominal pain, shakiness/tremors, sweating, fever, chills, or headache.

        • The signs or symptoms of cannabis withdrawal cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.

        • The signs or symptoms of withdrawal are not attributable to another medical condition and are not better explained by another mental disorder, including intoxication or withdrawal from another substance.

      • Cannabis (or a closely related substance) is taken to relieve or avoid withdrawal symptoms.

    • Specify if:

      • In early remission: After full criteria for cannabis use disorder were previously met, none of the criteria for cannabis use disorder have been met for at least 3 months but for less than 12 months (with the exception that the criterion, "Craving, or a strong desire or urge to use cannabis," may be met).

      • In sustained remission: After full criteria for cannabis use disorder were previously met, none of the criteria for cannabis use disorder have been met at any time during a period of 12 months or longer (with the exception that the criterion, "Craving, or a strong desire or urge to use cannabis," may be met).

    • Specify if:

      • In a controlled environment: This additional specifier is used if the individual is in an environment where access to cannabis is restricted.

About 9% of cannabis (pot) users become addicted to it. High levels of cannabis use are related to poorer educational outcomes, lower income, greater welfare dependence and unemployment and lower relationship and life satisfaction.

Effective Therapies

There is no FDA-approved pharmacological treatment for cannabis dependence. There are only two pharmacological, randomized, double-blind, placebo-controlled clinical trials which had a positive outcome (N-acetylcysteine, gabapentin) - but neither of these clinical trials has been replicated.

There are no randomized, placebo-controlled clinical trials of any psychosocial treatment. Thus the effectiveness of psychosocial treatment for this disorder is unknown.

Ineffective Therapies

Few individuals addicted to cannabis seek treatment. Even with treatment, fewer than 20% achieve long-term abstinence. Some argue that cannabis should be decriminalized, and that cannabis addiction should be treated "like any other medical disorder". They forget that there is no treatment for cannabis addiction that has been proven effective.

It is possible to stop using cannabis. To do this you must: (1) totally divorce yourself from drug-using or drug-supplying people, (2) not use alcohol or any other illegal drug, (3) be socially active and help others, (4) talk to other people who have successfully stayed off drugs, (5) devote yourself to important activities that give meaning and purpose to life (e.g., family, friends, sports, work, helping others, church etc.). Therapists know that these 5 steps work, but our therapies often are ineffective in motivating patients to complete these essential steps to recovery.

Cannabis And Schizophrenia

Cannabis (pot) has been proven to nearly quadruple the risk of developing schizophrenia. In 1969-70, Swedish military conscripts (>97% of the country's male population aged 18-20) were followed for 35 years. At the start of this study, none of the conscripts had schizophrenia. Over 35 years, those who had used cannabis more than 50 times at the beginning of the study had 3.7 times the normal rate of developing schizophrenia. This association was not explained by use of other psychoactive drugs or personality traits. Schizophrenia normally occurs in 1% of the population. 86% of individuals with schizophrenia are disabled and unemployed. Thus, if cannabis was legalized, the prevalence of schizophrenia could more than triple. This would cause a massive increase in the national unemployment rate.

Legalizing Illicit Drugs

Some people argue that illicit drugs should be legalized to decrease the crime associated with these drugs. Historically, tobacco and alcohol were once illegal drugs. Tobacco smoking is now the leading cause of death in America, and alcoholism is the third leading cause of death. Thus legalizing illicit drugs does not make them any less medically and socially harmful. In fact the opposite is true; legalizing illicit drugs increases their use and the harm they cause. The Government of Finland is passing legislation that will gradually ban all tobacco use by 2040.

Top 20 Most Harmful Drugs In Britain In 2008

Professor David Nutt published in the Lancet the following rating of Britain's most dangerous drugs. They are listed in descending order from the most harmful.

1. Heroin

Class A drug. Originally used as a painkiller and derived from the opium poppy. There were 897 deaths recorded from heroin and morphine use in 2008 in England and Wales, according to the Office of National Statistics (ONS). There were around 13,000 seizures, amounting to 1.6m tonnes of heroin.

2. Cocaine

Class A. Stimulant produced from the South American coca leaf. Accounted for 235 deaths -- a sharp rise on the previous year's fatalities. Nearly 25,000 seizures were made, amounting to 2.9 tonnes of the drug.

3. Barbituates

Class B. Synthetic sedatives used for anaesthetic purposes. Blamed for 13 deaths.

4. Street methadone

Class A. A synthetic opioid, commonly used as a substitute for treating heroin patients. Accounted for 378 deaths and there were more than 1,000 seizures of the drug.

5. Alcohol

Subject to increasing concern from the medical profession about its damage to health. According to the ONS, there were 8,724 alcohol deaths in the UK in 2007. Other sources claim the true figure is far higher.

6. Ketamine

Class C. A hallucinogenic dance drug for clubbers. There were 23 ketamine-related deaths in the UK between 1993 and 2006. Last year there were 1,266 seizures.

7. Benzodiazepines

Class C. A hypnotic relaxant used to treat anxiety and insomnia. Includes drugs such as diazepam, temazepam and nitrazepam. Caused 230 deaths and 1.8m doses were confiscated in more than 4,000 seizure operations.

8. Amphetamine

Class B. A psychostimulant that combats fatigue and suppresses hunger. Associated with 99 deaths, although this tally includes some ecstasy deaths. Nearly 8,000 seizures, adding up to almost three tonnes of confiscated amphetamines.

9. Tobacco

A stimulant that is highly addictive due to its nicotine content. More than 100,000 people a year die from smoking and tobacco-related diseases, including cancer, respiratory diseases and heart disease.

10. Buprenorphine

An opiate used for pain control, and sometimes as a substitute to wean addicts off heroin. Said to have caused 43 deaths in the UK between 1980 and 2002.

11. Cannabis

Class B. A psychoactive drug recently appearing in stronger forms such as "skunk". Caused 19 deaths and there were 186,000 seizures, netting 65 tonnes of the drug and 640,000 cannabis plants.

12. Solvents

Fumes inhaled to produce a sense of intoxication. Usually abused by teenagers. Derived from commonly available products such as glue and aerosol sprays. Causes around 50 deaths a year.

13. 4-MTA

Class A. Originally designed for laboratory research. Releases serotonin in the body. Only four deaths reported in the UK between 1997 and 2004.

14. LSD

Class A. Hallucinogenic drug originally synthesised by a German chemist in 1938. Very few deaths recorded.

15. Methylphenidate

Class B drug. Brand name of Ritalin. A psychostimulant sometimes used in the treatment of attention deficit disorders.

16. Anabolic steroids

Class C. Used to develop muscles, notably in competitive sports. Also alleged to induce aggression. Have been blamed for causing deaths among bodybuilders. More than 800 seizures.

17. GHB

Class C drug. A clear liquid dance drug said to induce euphoria, also described as a date rape drug. Can trigger comas and suppress breathing. Caused 20 deaths and 47 seizures were recorded.

18. Ecstasy

Class A. Psychoactive dance drug. Caused 44 deaths, with around 5,000 seizures made.

19. Alykl nitrites

Known as "poppers". Inhaled for their role as a muscle relaxant and supposed sexual stimulant. Reduce blood pressure, which can cause fainting and in some cases death.

20. Khat

A psychoactive plant, the leaves of which are chewed in east Africa and Yemen. Also known as qat. Produces mild psychological dependence. Its derivatives, cathinone and cathine, are Class C drugs in the UK.


Scientists Show Link Between Cannabis And Schizophrenia

  • Overview of substance abuse and overdose - Epocrates Online
  • Cannabis Dependence World Health Organization ICD-10 (2010)
  • Marijuana intoxication - PubMed Health
  • Cannabis Dependence - Wikipedia
  • Cannabis Abuse - DSM-IV Diagnostic Criteria, American Psychiatric Association
  • Cannabis Dependence - DSM-IV Diagnostic Criteria, American Psychiatric Association
  • Cannabis Intoxication - DSM-IV Diagnostic Criteria, American Psychiatric Association
  • Cannabis Intoxication Delirium - DSM-IV Diagnostic Criteria, American Psychiatric Association
  • Cannabis-Induced Anxiety Disorder - DSM-IV Diagnostic Criteria, American Psychiatric Association
  • Cannabis-Induced Psychotic Disorder - DSM-IV Diagnostic Criteria, American Psychiatric Association
  • Marijuana Abuse - National Institute On Drug Abuse
  • Cannabis: a health perspective and research agenda - World Health Organization
  • CBC Documentary: "The Downside of High"
  • Legalizing cannabis could almost double the national unemployment rate. Cannabis use has been shown to at least quadruple the risk of developing Schizophrenia. Schizophrenia is normally seen in 1% of the population, and is a lifelong illness. More than 90% of individuals with Schizophrenia are disabled and unemployed. Schizophrenia is the main cause of disability in adolescence, and is the 4th leading cause of disability for ages 15-44 in the developed world. Thus legalizing cannabis could result in 4% of the population having Schizophrenia; with 90% of these individuals being unemployed and needing disability pensions. This would almost double the national unemployment rate.
  • Cognitive function as an emerging treatment target for marijuana addiction. (2010) Both acute and chronic exposure to cannabis are associated with dose-related cognitive impairments, most consistently in attention, working memory, verbal learning, and memory functions.
  • Cannabis abuse and addiction: a contemporary literature review. (2009) There is increasing evidence that prolonged exposure to drugs of abuse including cannabis, produces long-lasting effects in cognitive and drug-rewarding brain circuits. Hence, addiction is now generally considered a chronic brain disease. Chronic use of cannabis impairs cognitive functions, perception, reaction time, learning, memory, concentration, social skills and control of emotions. There may also be panic reactions, hallucinations, paranoid states with fixed delusions and even acute psychosis. These impairments have obvious negative implications for the operation of a motor vehicle or machinery and performance at school or workplace as well as the development of a healthy family, a strong national economy and a secure society.
  • The adverse health effects of cannabis use: what are they, and what are their implications for policy? (2009) The evidence strongly suggests that cannabis can adversely affect some users, especially adolescents who initiate use early and young adults who become regular users. These adverse effects probably include increased risks of: motor vehicle crashes, the development of cannabis dependence, impaired respiratory function, cardiovascular disease, psychotic symptoms, and adverse outcomes of adolescent development, namely, poorer educational outcomes and an increased likelihood of using other illicit drugs.


Free Diagnosis Of This Disorder

Rating Scales


  • Cannabis Dependence Treatment Guidelines
  • Does Teen Drug Rehab Cure Addiction or Create It?
  • State of the art treatments for cannabis dependence. (2012) Few people who might benefit from treatment actually receive it. Among those who undergo treatment in randomized trials, long-term abstinence is achieved by fewer than 20%. The efficacy of twelve-step programs in cannabis dependence has not been examined. Pharmacologic treatments are under development, but none have yet been firmly established. A recent meta-analysis of psychosocial interventions for illicit substance use disorders found that treatments for cannabis dependence had comparatively larger effect sizes than treatments for other substance use disorders. Combination therapies have proven most effective, particularly those that begin with a motivational intervention, utilize incentives to enhance the commitment to change, and teach behavioral and cognitive copings skills to prevent relapse. Among adolescents, family engagement and collaboration with community stakeholders adds substantial value. Although only 9% of cannabis users develop cannabis dependence, the volume of people who smoke cannabis ensures that the total number of people in need of help is larger than the capacity of substance abuse specialty services.
  • Substance use disorder among people with first-episode psychosis: a systematic review of course and treatment. (2011) Nine studies without specialized substance abuse treatment and five with specialized substance abuse treatment assessed the course of substance use (primarily cannabis and alcohol) after a first episode of psychosis. Many clients (approximately half) became abstinent or significantly reduced their alcohol and drug use after a first episode of psychosis. The few available studies of specialized substance abuse treatments did not find better rates of abstinence or reduction.
  • Antipsychotic agents for the treatment of substance use disorders in patients with and without comorbid psychosis. (2010) Although there is some preliminary evidence that atypical antipsychotic agents may be effective in treating substance dependence, results have been mixed, with some studies demonstrating positive and others negative or no effect. Studies in patients with comorbid psychosis suggest that atypical antipsychotic agents, especially clozapine, may decrease substance use in individuals with alcohol and drug (mostly cannabis) use disorders. Atypical antipsychotic agents are not effective at treating stimulant dependence and may aggravate the condition in some cases.
  • A meta-analytic review of school-based prevention for cannabis use. (2010) The results from the set of 15 studies indicated that these school-based programs had a positive impact on reducing students' cannabis use (d = 0.58, CI: 0.55, 0.62) compared to control conditions. Programs that were longer in duration (=15 sessions) and facilitated by individuals other than teachers in an interactive manner also yielded stronger effects. The results also suggested that programs targeting high school students were more effective than were those aimed at middle-school students.
  • Treatment of cannabis use disorders in people with schizophrenia spectrum disorders - a systematic review. (2009) Contingency management was only effective while active. Pharmacological interventions appeared effective, but lacked randomized controlled trials (RCTs). Psychosocial interventions, e.g. motivational interviewing and cognitive behavior therapy (CBT), were ineffective in most studies.

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