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Cannabis Dependence and Adolescent Addiction Treatment

Marijuana is by far the most widely used illicit drug by adolescents. In the past few years, marijuana use by teens has been increasing while perceived risk of marijuana use has shown steady declines. In 2013, at Muir Wood Adolescent and Family Services, a gender-specific residential treatment program for boys aged thirteen to seventeen in northern California, the majority of teens entering residential treatment were admitted with a diagnosis of cannabis dependence. Recent studies by Monitoring the Future (Johnston, O’Malley, Bachman, & Schulenberg 2013) have shown that adolescent males are more likely to use marijuana than females, that males had an earlier age of onset, and that males are more likely than females to become marijuana dependent. 
Research into the effects of cannabis on the developing brain has increased exponentially over the past decade, largely as a result of discovering the importance of the naturally occurring cannabinoid system that regulates brain growth and development (Berghuis et al., 2007; Heng, Beverley, Steiner, & Tseng, 2011). This system has natural receptors for cannabis-like signal molecules produced in the body. These signals are used for development of healthy adolescent brain structures and function. The disruptive effects of external cannabis on the development of healthy adolescent brain function and structure are potentially very concerning and far reaching (Keimpema, Mackie, & Harkany, 2011; Rochetti et al., 2013; Moore et al., 2007; Hall & Degenhardt, 2009).
Cannabis, or marijuana, is a complex plant containing a wide variety—at least eighty-five—of chemicals called cannabinoids. Cannabinoids exert their psychoactive properties by interacting with the brain’s cannabinoid CB1 receptors, which are found in the brain in higher concentrations than any other receptor, and the endocannabinoid system, which is at least ten times the size of the endorphin system (Cermak, 2010) to repress the release of neurotransmitters. 
Anandamide is the naturally occurring molecule that binds to the brain’s natural cannabis receptor, modulating the receptor’s function. The problem with externally consumed cannabis is its nonspecific flooding of the naturally regulated endogenous system, which emulates and alters the endogenous neurotransmitter system, the same way that external administration of thyroxin can shut down the naturally occurring internal production of thyroid hormone. This alteration in the hormonal neurofeedback loop is the basis for cannabis dependence and withdrawal. 
The endocannabinoid system regulates such necessary physiological functions as appetite, memory, pain threshold, attention, fear/anxiety, and others (Cermak, 2010). This internal system is altered by ingesting cannabis, whose psychoactive cannabinoid THC produces euphoria and anxiety relief, increased appetite, higher pain threshold, and other symptoms in many; some, depending on their individual genetic and neurobiological makeup, will experience these effects differently. 
Chronic use of cannabis, however, can suppress this naturally occurring cannabinoid system, leading to dependence, tolerance, and withdrawal when the drug is stopped, and progress to drug-seeking behavior, often with adverse consequences. Therefore, cannabis dependence qualifies as a psychoactive drug addiction and is so characterized both by the American Society of Addiction Medicine (ASAM) and by the American Psychiatric Association (APA) in the new DSM-5. 
As with other substances, the diagnosis of dependence involves significant intrusion of the substance into a patient’s life, with clinically significant impairment in function in multiple areas. In the adolescent population, that impairment may manifest itself in impairment in school, peer and family relationships, as well as basic emotional, cognitive, and psychological function. Accordingly, the diagnoses of cannabis dependence and cannabis withdrawal have recently been added to the accepted psychiatric and medical literature (Budney, Hughes, Moore, & Vandrey, 2004; Budney & Hughes, 2006; Ramesh, Schlosburg, Wiebelhaus, & Lichtman, 2011). The severity of the cycles of intoxication and withdrawal in cannabis dependence are now recognized internationally as quite significant (Danovitch & Gorelick, 2012).
As stated in the DSM-5 (APA, 2013), “Cannabis use disorder is a problematic pattern of cannabis use leading to clinically significant impairment or distress” which could manifest by at least two symptoms within a twelve-month period. Some of symptoms listed by the DSM-5 include cannabis “taken in larger amounts or over a longer period than was intended,” “persistent desire or unsuccessful effort to cut down or control” use, “craving, or a strong desire or urge to use,” and “continued cannabis use despite having persistent or recurrent social or interpersonal problems exacerbated by the effects of cannabis” (APA, 2013). 
The growing problem of cannabis dependence in youth is posing an increasing challenge to adolescent addiction treatment programs. Part of this challenge is the prevailing belief in the youth drug culture that marijuana is a safe drug that has medical utility, which researchers are increasingly finding may be true. Similarly, prescription opiates are medically useful, but have potentially dire consequences when misused. 
The CB1 receptors—which are broadly distributed throughout the brain, but selectively activated during adolescence for healthy brain structure development—show disruption in their function when flooded by internal cannabinoid exposure. The result can be altered structure and function of brain regions that control emotion, thought, memory, and social interaction (Van Laere et al., 2009). These changes can persist well into adulthood and increase risk for psychiatric illness as well as other drug addiction (Chadwick, Miller, & Hurd, 2013). 
Cannabis is the most commonly used substance in the adolescent population between eighth and twelfth grade, recently surpassing even the use of cigarettes (Johnston et al., 2013; Chadwick et al., 2013). The prevalence of twelfth grade students who have used marijuana in the past month is roughly 25 percent, and those who have used it within the past year is roughly 35 percent (Johnston et al., 2013). Among first time cannabis users, 2 percent will develop addiction within a year, with that number increasing to 6 percent after a decade of continuous use (Lopez-Quintero et al., 2011). Each year 1.5 percent of Americans struggle with addiction to cannabis and 17 percent of admissions for treatment are for cannabis dependence (SAMHSA, 2012). However, over half of cannabis admissions are for those twenty-five years of age or younger, so clearly this is a problem that disproportionately affects youth, contributing to early onset addiction. Parental referral may affect this statistic, since parents are more able to direct adolescents than their adult children. 
As with alcoholism, one of the challenges facing the individual is that the drug of abuse is so widely used and accepted in society. Cannabis is the most widely used illicit substance in the United States. Results from the 2010 National Survey of Drug Use and Health indicate that 7 percent of the population uses marijuana compared to less than 1 percent for cocaine, heroin, and methamphetamine combined (SAMHSA, 2011). The risk of developing cannabis dependence in adulthood for users that begin smoking at age eighteen is approximately 9 percent (Budney, Roffman, Stephens, & Walker, 2007), however that risk is doubled in users that begin smoking in childhood or adolescence, and can be tripled, as high as 35 to 40 percent, for daily users under eighteen (Winters & Lee, 2008; Kandel & Davies, 1992).
The young person who is suffering negative health and behavioral consequences as a result of his or her chronic and compulsive cannabis use is a significant clinical and public health problem. 
Despite the widespread use of cannabis in our society, the overall incidence of cannabis use remains constant with prescription drug abuse as more of a growing drug problem among young people. With the relatively constant incidence of cannabis use, why has dependence increased? It is clear that a major factor is a substantially higher potency of THC in current engineered marijuana being consumed. Since 1983, when THC concentrations averaged below 4 percent, many marijuana samples now reflect content in the 10 to 20 percent range, with some specialty products showing concentrations exceeding 30 percent (Meserve & Ahlers, 2009). Specialty products seen in adolescent treatment include “earwax” aka “dabs,” which hash oil extracted using alcohol heated with a butane flame. Dabs has a THC concentration of as much as 80 percent (Doan, 2013). This powerful product has been known to induce psychotic breaks, hallucinations, and phantom tactile sensations, to say nothing of the potential danger of fire and explosion in its hazardous production method (Doan, 2013). 
Acute intoxication with potent forms of marijuana has long been described (Smith, 1969), with effects varying depending on the physical and psychological characteristics of the individual and the environment in which the drug taking occurs. The complexity of the interplay of these variables means that many patients seeking treatment present as dual diagnosis patients with both cannabis dependence and comorbid psychiatric disorders. Twenty-three percent of patients with psychosis are current cannabis users (Green, Young, & Kavanagh, 2005). Although many patients coming into treatment may in effect be using marijuana to self-medicate, their underlying psychopathology and the medications they’re on combine to create a synergistic effect that can be very destructive, particularly if they are misusing medications such as psychostimulants such as Adderall, or combining marijuana with alcohol in a social setting. A study by Dennis and colleagues determined that thirty-six percent of teens seeking treatment for cannabis use disorder had internalizing disorders such as depression or anxiety, and 59 percent had externalizing problems such as conduct disorder and ADHD (2004). Cannabis can relieve anxiety in the short-term and be perceived as a benefit to the user, but can aggravate or precipitate comorbid psychopathology in the long-term, particularly in younger users when the adolescent brain is still maturing (Amen & Smith, 2010).
Adults entering treatment for cannabis use disorder typically have been using cannabis on a daily basis for ten years and report multiple serious attempts to stop. The consequences of their marijuana use include relationship problems, financial difficulties, low self-esteem, and impaired productivity associated with sleep and memory problems (Stephens, Babor, Kadden, & Miller, 2002). Most report that they experience withdrawal symptoms when they try to stop. 
Initially, youth are not interested in recovery but are in fact seeking to moderate their use rather than quit using marijuana completely (Lozano, Stephens, & Roffman, 2006). However, little empirical evidence exists about such harm reduction approaches for cannabis dependence, where harm reduction does not seek abstinence per se but rather focuses on reducing the harm associated with substance use. A state of the art addiction treatment program, such as Muir Wood Adolescent & Family Services in Petaluma, CA, embraces a well-established abstinence- and recovery-based model which focuses on managing the medical and psychiatric consequences of cannabis abuse, detoxification from the drug, and participation in a psychosocial program embracing youth-oriented recovery support groups and education for both residents and parents. 
Teens and young adults entering treatment do not as readily admit problems related to their cannabis dependence, although they are at increased risk for a myriad of problems including sexually transmitted diseases, unplanned pregnancies, low educational achievement, early dropout rates, delinquencies, and legal entanglements (Tims et al., 2002). Using an abstinence and recovery model, cannabis-dependent youth respond to the same types of psychosocial therapies used for opiate dependence and other substance use disorders, including motivational enhancement therapy, cognitive behavioral therapy, and contingency management; combining these three modalities yields the best results when abstinence is the goal (Peters, Nich, & Carroll, 2011). 
Muir Wood has established specific protocols for the treatment of cannabis dependent youth and dual diagnosis patients. It is crucial that a multidisciplinary team, including a psychiatrist, begin with an evaluation when the presenting problem is cannabis. 
We must keep in mind that even without substance use, adolescence is a period where the greatest number of psychiatric disorders first present. The twelve month prevalence of psychiatric illness is 40 percent in adolescents compared to 25 percent in adults, highlighting the vulnerability of the developing adolescent brain to substance exposure broadly, and, as discussed above, to cannabis exposure specifically (Chadwick et al., 2013; Heng et al., 2011).
Therefore, from a clinical psychiatric perspective, the correlation between adolescent cannabis use and psychiatric illness is an area of great concern and urgent clinical investigation (Chadwick et al., 2013). Areas of inquiry include: vulnerability to other substance addictions, depression and suicide, anxiety, cognition, memory, psychosis, and problems with personality and psychosocial development. Current research indicates potentially significant correlation in all areas (Degenhardt et al., 2013; Fergusson, Horwood, & Swain-Campbell, 2002; Fergusson, Boden, & Horwood, 2006; Ferdinand et al., 2005; Moore et al., 2007; Winters, Stinchfield, Lee, & Latimer, 2008; Galéra et al., 2013). This increasing understanding lends special consideration to the diagnosis and treatment of cannabis use disorders in the adolescent population. 
With that in mind, we can now consider the importance of a broad-based psychiatric assessment for the cannabis dependent client at Muir Wood, particularly given the prevalence of cannabis dependence in excess of 80 percent of admissions to date.
The psychiatric protocol begins by constructing a case formulation with biopsychosocial underpinnings (Winters, Hanson, & Stoyanova, 2007; Perry, Cooper, & Michels, 1987). In contrast to a typical review of systems and reduction toward diagnostic-driven treatment algorithms, the case formulation is structured to keep clinical attention open and flexible to unfolding information. The construct of the formulation is well developed, and has three essential components: evaluation of external, nonpsychological problems, early assessment of the individual psychology of the client, and early prediction of the client’s response to treatment. Most importantly, the case formulation is designed to evolve throughout the course of treatment.
In the treatment of cannabis dependence, the hallmark example of an external problem in treatment at Muir Wood is cannabis withdrawal, which occurs acutely upon admission and lasts up to several weeks. At the time of admission, we routinely see extremely high levels of blood THC, due to the exponentially increasing potency of available cannabis street products (Atakan, 2012; Cascini, 2012). This in turn leads us to the management of cannabis withdrawal, which occurs over the first forty-five days of treatment.
Symptoms of cannabis withdrawal include anxiety, irritability, depressed mood, restlessness, disturbed sleep, decreased appetite, and gastrointestinal disturbances. Treatment for cannabis withdrawal does not yet have an evidence-based protocol (Budney et al., 2004; Budney & Hughes, 2006; Allson, Norberg, Copeland, Fu, & Budney, 2011). However, several medications classes are under investigation, with the strategy of influencing the brain circuits that mediate cannabis intoxication and withdrawal. Examples we can use in the adolescent population are trazadone and nefazadone for sleep disturbance, and clonidine for anxiety and agitation (Danovitch & Gorelick, 2012). These medications can be used safely and for short periods in the initial phases of cannabis withdrawal at Muir Wood.
As with all substance use disorders, cannabis dependence carries a wide range of additional external factors that demand clinical consideration. These range from comorbid psychiatric conditions such as unipolar or bipolar depression, anxiety, psychosis, attention and learning disorders, to acute academic and legal problems, emotional and psychological conflicts, social conditions, family dynamics, and the stressors inherent in adolescent development (Patton et al., 2002). Therefore, the case formulation includes medically-assisted treatment and close monitoring of external symptoms as the course of withdrawal progresses. 
The internal aspects of the client take on equal significance in the case formulation. The psychiatrist must pursue an understanding of the client’s internal emotional conflicts, resistances, wishes, and fears in an ongoing fashion to establish a therapeutic alliance (Horvath & Luborsky, 1993; McWilliams, 2011). A good therapeutic alliance is important for early retention and for ongoing collaboration, trust, disclosure, and more accurate assessment of each client’s individual needs. 
All psychiatric evaluation and case formulation should evolve collaboratively with the multidisciplinary treatment team, as well as with the client and family. From a psychiatric perspective, this mandates ongoing evaluation of affect, cognition, and overall psychological wellbeing, which the psychiatrist conducts at the individual and group therapy level in the treatment setting. Hence, the evaluation is dynamic, as the course of cannabis withdrawal evolves in conjunction with the broader emotional and cognitive changes that invariably occur over the course of a multidisciplinary family based treatment. Specific medication considerations, as well as other psychiatric treatment considerations, including specific psychotherapies, require continuous reassessment of the client and dialogue with the family. Finally, the formulation must evolve with consideration of a useful interface with longer-term treatment settings at the time of discharge to other levels of care.
As demonstrated by the following case study, cannabis dependence may be the primary problem or it may be secondary with significant psychopathology being the main therapeutic issue.
A Case Study  
By Jennifer Golick, LMFT  
Robert was admitted to treatment for marijuana dependence. He began using marijuana at age fifteen, beginning with periodic use with friends and culminating with smoking alone several times daily. He was admitted to treatment after his parents found drug paraphernalia in his “clubhouse,” a gardening shed that he had constructed to isolate and use in his back yard.
Robert is the son of two professionals, an attorney and a finance manager. He was adopted at birth through an out of state adoption agency. He has a younger sister who is also adopted. Both adoptions were closed and the adoptive parents were avoidant of discussing the details of the adoption with either child. His mother presents as highly anxious and father presents as analytic and somewhat overwhelmed by affective expressions of emotion. Neither parent has a family history of addiction.
Robert’s marijuana use escalated in conjunction with several life stressors at approximately age sixteen. One primary stressor was the transfer of schools. Robert experienced bullying at his public school and initiated a transfer to a private academy in the hopes of forming healthier peer relationships. This goal was not met and he perceived experiencing the same disenfranchisement and social isolation that he’d experienced at his public school. The second stressor was being contacted by his biological mother via social media. Due to the nature of the closed adoption and the lack of familial context given to Robert about the details of his adoption, this created an internal conflict with regards to his identity and curiosity of his biological family of origin. His use of marijuana escalated to multiple times daily and he admitted to smoking up to a gram a day of medicinal-grade marijuana. He isolated from his family, spending hours and sometimes overnight in the garden shed in the backyard of his family home.
During the course of treatment, which included a combination of CBT, motivational interviewing and weekly family therapy, the entire family participated in Muir Wood’s Intensive Family Education Program, which included a combination of didactic instruction about topics germane to cannabis dependence and family dynamics, as well as a therapist-facilitated Multi Family Process group. In addition, they participated in weekly family therapy where the dynamics of the relationships within the family were explored in greater depth. During this process, Robert was able to address his mother’s anxiety and emotional fragility as being problematic for him, as he felt responsible for her affective instability. By extension, the father was able to discuss his anger toward Robert and identified that he felt powerless when the mother became so emotionally overwrought, and as a result, directed that anger toward Robert as being the cause of her upset. It was discovered that throughout the family, they were reacting to one another based upon their assumptions of situations, often wrongly, which lead to further chaos and conflict within the house. During individual family therapy, parents received much coaching from the therapist on how to set limits and engage in more direct and healthy communication. Additionally, they were able to minimize pathologizing Robert’s behavior and established a baseline for what was “normal” adolescent behavior versus perceived disordered behavior. Both parents participated in weekly Al-Anon meetings and learned about addiction and codependency from that perspective. 
Upon discharge, the family was able to engage in difficult and historically conflict-inducing discussion with positive outcomes. This included a discussion of what to do with the “clubhouse,” which was a point of great conflict historically. What was once viewed as the epicenter of his drug using behavior and isolation, the “clubhouse” was repurposed as a garden tool storage area that everyone had access to. Both parents were also able to detach from a pattern of micromanagement based out of fear and moved to a place of supporting Robert’s recovery through his involvement in Twelve Step groups and work with a sponsor. Following discharge, the whole family remained in contact with the treatment program as a means of peripheral support while engaging the resources in their community.
In summary, the potential harm of cannabis use in adolescence is becoming increasingly clear, as is the need for effective treatment. The treatment of cannabis dependence and cannabis withdrawal is rapidly evolving, though it currently lacks standard evidence-based treatment protocols. Therefore, at present, we must do our best to construct treatment plans that correlate broad scientific considerations with the specific presentation of each adolescent and family. 
Muir Wood’s psychiatric strategy is to construct a formal, broad-based case formulation that takes into account external problems for the client and family, as well as the internal and interpersonal psychology of the client and family. The case formulation is fundamentally designed to evolve. This design is particularly important in the treatment of cannabis dependence, where clinical presentation evolves quite dynamically over the course of a residential treatment. 
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