Up until the last few years, the prevailing opinion was that can-nabis use did not produce addiction and dependence and that can-nabis users could discontinue use without the help of treatment programs. In fact, this was the prevailing attitude even amongst users, many of whom had tried unsuccessfully to discontinue use (Weiner et al., 1999). Although it is undeniably true that the ma-jority of cannabis users are able to stop without assistance, it is also becoming apparent that many cannabis-dependent individu-als cannot stop without help. The generally held opinion among cannabis users is that there are few substance abuse programs that will accept them if their primary substance is cannabis and that those programs that do exist are not effective for cannabis users (Weiner et al., 1999).
However, mounting evidence documents the existence of a population of cannabis-dependent individuals who desire treatment (Roffman and Barnhart, 1987; Budney et al., 1999; Stephens et al., 1993a, 1993b, 1994, 2000; Weiner et al., 1999). For example, a survey of 335 adolescent cannabis users reported that 80% had considered quitting, 52% had tried unsuccessfully to quit, and only 24% believed that they would never quit (Weiner et al., 1999). In one investigation, a public service announcement directed at chronic marijuana users resulted in interviews of 225 people who responded. It was found that 74% reported negative consequences of their marijuana use and 92% wanted to be treated (Roffman and Barnhart, 1987). In 1998, 48% of adolescent admis-sions to state-funded substance abuse programs were for primary cannabis dependence, indicating a significant need for treatment programs for cannabis dependence (SAMHSA, 1999).
With the recognition that cannabis use produces depend-ence and withdrawal, and that cannabis-dependent individuals may benefit from treatment, many substance abuse programs have started offering treatment to people whose primary drug of abuse or dependence is marijuana. Unfortunately, these pro-grams are not generally designed specifically for cannabis de-pendence and they have not achieved high success rates (Baer et al., 1998; Hser et al., 2001; Hubbard et al., 1985; SAMHSA, 2000). Similarly, many nonprofessional organizations that offer support groups, such as Alcoholics Anonymous (AA), Narcotics Anonymous (NA) and Self-Management and Recovery Training (SMART), have also begun to welcome people whose primary drug is cannabis. In addition, there is now a nonprofessional sup-port organization, Marijuana Anonymous (MA), started by and run for cannabis-dependent individuals.
We are aware of only four controlled studies of treatment of cannabis-dependent individuals. In three of the studies, the sub-jects were seeking treatment specifically for cannabis dependence, whereas the fourth study involved schizophrenic patients under-going treatment for marijuana dependence. The first study found no difference in the outcome between a cognitive–behavioral relapse prevention group and a support group – overall, 16% of subjects had decreased use and 15% were abstinent when assessed 12 months after treatment (Stephens et al., 1994). Higher quantity and frequency of marijuana use prior to treatment were strongly correlated with poorer outcome (Stephens et al., 1993b). A sec-ond study compared a motivational enhancement group, a moti-vational enhancement plus cognitive–behavioral therapy group, and a motivational enhancement plus cognitive–behavioral ther-apy group combined with a voucher-based incentive program that rewarded bi-weekly urine screens that were negative with vouch-ers for retail items. The group that received the voucher-based incentive program achieved a higher rate of abstinence during the study period and at the end of the study than either of the other two treatment groups (Budney et al., 2000). Similar success using monetary rewards for negative urines was also reported in a small trial of schizophrenic patients undergoing treatment for marijuana dependence (Sigmon et al., 2000). The last study compared brief motivational therapy with a cognitive–behavio-ral relapse prevention support group and a control group consist-ing of subjects put on a waiting list. Although no difference was found between the two active-treatment groups, subjects in both treatment groups were using significantly less marijuana and re-ported significantly fewer symptoms of dependence and fewer marijuana-related problems than subjects in the control group. Nevertheless, only 22% of the subjects in the active-treatment groups remained abstinent throughout a 16-month follow-up pe-riod (Stephens et al., 2000).
The strongest predictor of successful outcome is longer retention in treatment programs (Simpson, 1981). Predictors of dropping out of an outpatient treatment program and presumably continuing use, were found to be young age, financial difficulties and psychological stress (Crits-Christoph and Siqueland, 1996; Grella et al., 1999; Hser et al., 2001; Simpson et al., 1997; Roffman et al., 1993). More research is clearly required to discover effec-tive ways to retain cannabis-dependent patients in treatment.
Currently, there are few substance abuse programs specifi-cally designed to treat cannabis dependence. Most programs are designed to treat all types of substance abuse, so that cannabis-dependent patients typically receive the same treatment as patients with other types of substance abuse. Since many cannabis-depend-ent patients are also dependent on other substances, this is often a satisfactory treatment strategy. Also, a number of basic principles of treatment of substance use disorders are equally applicable to cannabis dependence and other types of substance dependence.
One of these principles, critical for selecting the most ap-propriate intervention, is the importance of assessing an individ-ual’s stage in the recovery process (Prochaska and Velicer, 1997). Individuals in early stages, such as “precontemplation” and “con-templation”, benefit most from strategies aimed at using reliable sources to convey accurate information about cannabis that will help individuals identify personal reasons for discontinuing use. Individuals in later stages, such as “action” and “maintenance”, benefit most from cognitive–behavioral relapse-prevention strat-egies (Botvin, 2000; Prochaska and Velicer, 1997).
As with all other drugs of abuse, the ultimate goal in the treatment of cannabis dependence is abstinence. In a phenom-enon similar to that seen in alcohol-dependent people, many cannabis-dependent people have exposure to others who are able to use cannabis in a nonproblematic manner, and will often in-sist that their goal is to moderate their use, rather than cease use altogether. Unfortunately, if a person is susceptible to cannabis dependence, the most frequent outcome of trying to use moder-ately after a period of abstinence is that within a few weeks or months they have returned to their preabstinence pattern of use. Although physicians can tell cannabis-dependent people that this is the likely outcome, only after going through this process one or more times do people whose goal is moderation rather than abstinence recognize that like alcoholics, moderation is not an option for them. The process of treatment begins with detoxifi-cation followed by maintenance. As discussed in the section on etiology and pathophysiology, chronic users usually experience a withdrawal syndrome during detoxification. Since the cannabis withdrawal syndrome is not life-threatening, detoxification gen-erally does not require hospitalization unless it is complicated by detoxification from other drugs or by comorbid Axis I disorders that do require hospitalization for safe treatment. The intensity of the cannabis withdrawal syndrome varies widely, with some individuals reporting very mild symptoms and others report-ing more severe symptoms (Budney et al., 1999; Haney et al., 1999; Kouri and Pope, 2000; Kaymakcalan, 1973, 1981; Tennant, 1986; Compton et al., 1990; Jones et al., 1976, 1981; Jones, 1983; Wiesbeck et al., 1996).
To help a patient tolerate the 7- to 10-day withdrawal period, practitioners should provide psychological support (e.g., reassur-ance that the symptoms will resolve in a little over a week) and in some cases, provide pharmacological support (Miller et al., 1989; Haney et al., 2001a, 2001b). Research into possible pharmacologi-cal interventions is just getting underway. One author suggested the use of long-acting benzodiazepines if the level of discomfort is high or there are abnormal vital signs (Miller et al., 1989). A small placebo-controlled, crossover study of 10 subjects showed that the antidepressant bupropion (Wellbutrin, Zyban) worsened irritability, restlessness, depression and insomnia associated with marijuana withdrawal (Haney et al., 2001a). A second small placebo-controlled, crossover study of seven subjects showed that the antidepressant ne-fazodone (Serzone) decreased anxiety, muscle aches and restlessness associated with marijuana withdrawal, but not irritability or insomnia (Haney et al., 2001b).
The foundation of maintenance treatment, as with other types of substance use disorders, is regular attendance at groups that provide education and support. It is hypothesized that such groups are effective because fellow group members are best able to confront each other’s denial and minimization of the substance abuse problem and the rationalizations put forth by the substance abuser for continued use despite negative consequences. Also, substance users typically report that they are most likely to believe information if it is provided by former users (Weiner et al., 1999). Since cannabis dependence, like other types of substance abuse, is characterized by a chronic, relapsing course, these groups pro-vide an important function by addressing issues around relapse prevention and provide support for dealing with relapses when they do occur.