This 40 year old man has presented with an interesting constellation of symptoms: depressed mood, insomnia, irritability, and malaise. Given his history of heavy, prolonged cannabis use and recent attempt at quitting, these symptoms are strongly suggestive of withdrawal. However, note two important points in his evaluation - the presence of auditory hallucinations, and the family history of schizophrenia in a first degree relative. The incidence of substance misuse is much higher in individuals suffering from schizophrenia (as compared to the general population); furthermore, this patient has never had a proper psychiatric evaluation before. Thus, it is important to exclude the presence of coexisting schizophrenia. While his psychiatric evaluation reveals the presence of low self esteem, auditory hallucinations, impaired attention and concentration, and poor recent memory, these do not satisfy the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria for schizophrenia. However, these findings do satisfy the diagnostic criteria for cannabis use disorder and cannabis withdrawal. His evaluation should not stop here; it is vital to determine how severe the accompanying depression is, and quantify the degree of cognitive impairment; furthermore, a plan should be built up to rescue him from the the grip of cannabis. In this respect, the Beck Depression Inventory (BDI) reveals the presence of mild depression; the Mini Mental State Examination (MMSE) shows no deficits in cognition. In the short term, Dronabinol will help to relieve his withdrawal symptoms. In the long term, a combination of Motivational Enhancement Therapy (MET) and Cognitive Behavior Therapy (CBT) is important to obtain lasting results. Note that a Urine Enzyme Multiplied Immunoassay Technique (EMIT) Test is of no value in this individual, given that he freely admits to cannabis use. Furthermore, note that a negative result for this test in no way excludes the above diagnoses, as a few days abstinence is all that is needed to clear away any evidence of cannabis use from urine. Nor is there an indication for an electroencephalogram (EEG) in this individual. Electroconvulsive Therapy (ECT) does not play any role in the management of cannabis use disorder or cannabis withdrawal. Discussion Cannabis, widely known as marijuana, is an extremely popular recreational drug. Over time, it has accumulated many other names including pot, hash, herb, dope, herb, skunk, boom, gangster, grass, and ganja. While earlier considered an illegal substance, the drug has now been decriminalized in several states and countries. Cannabis is extracted from the flowering plant Cannabis sativa; tetrahydrocannabinol (THC) is the main active metabolite. Note that THC also has medicinal value, being approved in the treatment of a number of conditions including chemotherapy induced nausea and vomiting, and weight loss and vomiting associated with AIDS. When used as a recreational drug, cannabis is usually smoked or ingested; in recent years, new devices have been developed to vaporize cannabis. Understandably, smoking or inhalation of vapor produces the desired effects more rapidly. The potency of generally available cannabis is highly variable; reportedly there has been a steady increase in the potency of the seized cannabis over the last few years. According to the Diagnostic and Statistical Manual, Fifth edition (DSM-5) of the American Psychiatric Association (APA), cannabis related disorders are subclassified into 5 categories, which are individually discussed below. Each category has distinct diagnostic criteria, which are not detailed here due to space limitations; however, note that there is considerable overlap between each. Discussion: Cannabis Use Disorder By definition this is a problematic pattern of cannabis use leading to clinically significant impairment or distress. Overall, cannabis use disorder is more prevalent among males than in females, and in adolescents as compared to in adults; in all groups, the prevalence has gradually increased over the past few decades. The onset is most commonly during adolescence; this then progresses over an extended period of time. Adolescent users are predisposed to mood instability, altered energy levels, eating disorders and school related problems with a dramatic deterioration of their school performance. In adults, a well-established pattern of daily use regardless of detrimental psychosocial or health consequences is observed. Note also that a clear connection has been uncovered between cannabis use at an early age, and the predisposition to abuse other substances. Functional consequences of cannabis use disorder include amotivational syndrome, accident proneness, and risk taking behavior. Chronic abuse can lead to respiratory illnesses, increased risk of malignancies (due to chronic exposure to carcinogens) and various psychotic disorders, notably, schizophrenia and acute psychosis. The majority of adult users have repeatedly failed at cessation attempts, either succumbing to the strong desire, or in order to escape from the grips of withdrawal symptoms. While several biochemical tests have been devised to determine if an individual has recently used cannabis, almost all of these have issues with reliability and sensitivity. The enzyme multiplied immunoassay technique (EMIT) test is the cheapest and most commonly used investigation in this regard, and typically uses a cut-off limit of 50 ng/ml of tetrahydrocannabinol (THC) in urine. Discussion: Cannabis Intoxication Cannabis intoxication leads to a rapid and predictable set of symptoms and signs. These usually begin with a state of euphoria, followed by anxiety, impaired coordination, poor judgement and memory, and decreased alertness and disjointed thinking. In addition, undesirable side effects such as a dry mouth, persistent cough, and blood-shot eyes may be observed. The signs, symptoms and adverse effects unsurprisingly increase with higher doses and tend to be unpredictable when cannabis is ingested rather than smoked. Occasionally, cannabis abuse can lead to more serious consequences such as acute psychosis, myocardial infarction and sudden cardiac arrest. Benzodiazepines and cardiac monitoring comprise the management of critical cases. Discussion: Cannabis Withdrawal A substantial proportion of cannabis users report experiencing withdrawal symptoms following cessation of, or reduction in heavy prolonged use, with an equally significant number relapsing to cannabis use or initiating another drug to obtain relief from withdrawal symptoms. Features of withdrawal include irritability, depressed mood, insomnia, restlessness, anxiety and physical symptoms such as fever, chills, tremors, sweating and abdominal pain. Most symptoms occur during the first week following cessation or a significant reduction in the usual dose and may persist for 1 to 2 weeks, insomnia usually being the longest lasting of these. Withdrawal symptoms tend to be more severe and more common among adult users, presumably due to the longer durations of previous use. The symptoms are usually not sufficiently severe to necessitate medical care; note also that the synthetic cannabinoid Dronabinol has been shown to reduce their severity. Discussion: Other Cannabis-Induced Disorders There are certain cannabis-related clinical entities consisting of symptoms that are sufficiently severe to warrant an independent diagnosis. These include cannabis-induced psychotic disorder, cannabis-induced sleep disorder, cannabis intoxication delirium and cannabis-induced anxiety disorder.
Impairment of social, occupational, or other important areas of functioning that is caused by cannabis, but does not meet sufficient diagnostic criteria to be classified under any of the above categories come under this category. Overall, cannabis related disorders have shown promising results when behavioral treatment methods are applied. Motivational enhancement therapy (MET), cognitive-behavioral therapy (CBT), contingency management (CM, also known as systematic use of reinforcement), self help groups and family therapy have been used successfully. A combination of MET and CBT is more potent than any individual technique; the most productive outcome is likely to be obtained from an intervention that combines all three approaches (CBT, MET, and CM).