The 1936 propaganda film, “Reefer Madness”, urged parents to warn their kids that smoking marijuana caused reckless driving, sexual assault, violent behavior, permanent psychosis, and suicide. Dire outcomes and lurid scenes are dramatized to the hilt. The movie flopped, and was forgotten until its re-discovery by gleeful advocates of marijuana legalization in the 1970s. Its success as a camp hit on college campuses helped launch New Line Cinema and led to a musical on Broadway, with a film version due later this year.

Some might consider all this harmless fun but a series of compelling studies published in recent years shows that cannabis is an addictive substance. Some individuals do suffer harm from smoking pot— particularly youth who already have mild psychotic symptoms or have relatives with mood disorders with psychosis or schizophrenia (placing them at high risk genetically for these conditions). These findings are coming to light just as liberalization of marijuana laws is gaining ground, a change sure to ease access to marijuana. This may send the signal that pot is considered relatively benign by the authorities and further tempt risk-loving and impulsive adolescents.  It appears from these studies that marijuana can do serious harm to our children with bipolar disorder and their well siblings, and is far more likely to harm them than their peers.

"There is no question marijuana can be addictive; that argument is over," Dr. Nora Volkow, director of the National Institute on Drug Abuse, told the Los Angeles Times last year. "The most important thing right now is to understand the vulnerability of young, developing brains to these increased concentrations of cannabis." 

While most of the recent studies link marijuana with schizophrenia, some researchers stress that it is the presence or history of psychotic symptoms in a young person or their relatives, rather than diagnosis, that puts them at increased risk.  “I think the evidence that cannabis and other drugs can trigger psychosis is convincing and that it applies to psychosis broadly, not only schizophrenia,” says Stephen V. Faraone, Ph.D., who directs both the Medical Genetics Research Program and Child and Adolescent Psychiatry Research at SUNY Upstate Medical University in Syracuse, New York.

Psychotic symptoms are found in about 20% of adults with bipolar disorder, but appear far more common in children, a subgroup thought to have a more severe form of the illness.  In an NIMH-funded study of child mania, Barbara Geller, M.D. and colleagues at Washington University in St. Louis reported that nearly 60% of pre-adolescent subjects with mania had psychotic symptoms (including grandiose delusions) (Geller, 2004).   Symptoms of psychosis include such things as hearing voices and seeing things that aren’t there, believing one is being spied on or followed or that one is receiving personal messages through the media, having emotions that are inappropriate to the situation (laughing while describing a sad event), and bizarre or disorganized appearance, dress, or behavior (being overly excited, angry, or entirely unresponsive to others).

Why might smoking marijuana be more harmful to teenagers with bipolar disorder and past or present symptoms of psychosis, than their friends?

In “Ten Myths about Marijuana—The Truth About Ten Popular Misconceptions,” the White House Office of National Drug Control Policy points out that:

• Short term effects of marijuana use include memory loss, distorted perception, trouble with thinking and problem solving, and anxiety [--already problems for most kids with bipolar disorder].  
• Students who use marijuana may find it hard to learn, thus jeopardizing their ability to achieve their full potential [--learning difficulties are already present in  many kids with bipolar disorder].
• Frequent marijuana users show deficits in math skills and verbal expression, as well as selective impairments in memory retrieval processes [--impairments in math, pragmatic language and memory are found in many kids with bipolar disorder].  

Smoking marijuana has negative chemical effects on the brain. It causes the release of an enzyme that increases dopamine, a chemical already dysregulated in the brains of people with psychotic symptoms. In 1990, researchers discovered that the human brain has receptors for cannabinoids.  A compound in marijuana called THC acts on the human cannabinoid CB1 receptor gene which happens to be located on chromosome 6q the same location where geneticists suspect susceptibility genes for both bipolar disorder and schizophrenia may be found. The THC in marijuana sold now is many times stronger than that sold in the 60s and 70s.  Marijuana use can prevent psychiatric medications from working as they should. Teens abusing marijuana, alcohol or other street drugs are likely to appear nonresponsive to treatment even while taking their medications as prescribed.  Stability will be impossible while substance abuse continues. 

Large studies from Sweden (Andreassen, 1987), New Zealand (Arseneault, 2002), the Netherlands (van Os, 2002), and Germany (Henquet, 2005) have reported associations between marijuana use and increased rates of psychotic illness.  Other studies find an increased risk of suicidal ideation and suicide attempts (Wilcox, 2005) and motor-vehicle accidents (Kalant, 2004) associated with the drug. Among people with psychiatric illness, such as those who have been previously hospitalized for their illness, substance abuse is associated with increased violence.  (Steadman, 1998) 

Parents of kids with bipolar disorder (or with a family history of psychosis) must educate their children, from a young age, that they have a special inherited vulnerability (an invisible “Achilles heel”) to the negative effects of marijuana. It’s also important that parents learn the language and telltale signs of drug use (such as air fresheners, breath spray, rolling papers, cigarettes taken apart, extreme hunger after being out with friends, hysterical crying or shaking, money missing).  Other signs are nearly impossible to distinguish from the so-called negative symptoms of schizophrenia, which (during the approximate 5-year prodrome before the psychotic break, which typically occurs in late adolescence and early adulthood) include loss of ability to concentrate, loss of motivation, plunging grades and test scores, confusion, withdrawal, and increased hostility. A parent who notices these signs and symptoms should suspect substance abuse and have the child evaluated by a substance-abuse professional.  Some parents insist upon random urine screens (kits are available at any pharmacy) as a condition for continuing to live at home. Outpatient substance abuse treatment may help, but if not, or the teen refuses, then mandatory treatment in a dual-diagnosis residential program may be necessary. Some The Balanced Mind Foundation parents report that these programs saved their children’s lives, and teens often thank parents later for the intervention.

As the dire outcomes portrayed in “Reefer Madness” are being confirmed by scientific studies as real possibilities for our most vulnerable kids, the movie no longer strikes many of us as funny. Instead, we hear the voices of grieving parents crying out to us across a chasm of more than fifty years, trying to warn us about the horrors they saw firsthand. Back then, they thought all kids were at risk; now it seems it is our kids who are most at risk.  Despite the dated clothes, hairstyles, and over-the-top acting, the film’s message takes on a new urgency, one conveyed by its original title: Tell Your Children.

References:

Andreasson S, et al.  Cannabis and schizophrenia. A longitudinal study of Swedish conscripts.  Lancet 2 (1987) 1483-1486.

Arseneault L, et al. Cannabis use in adolescence and risk for adult psychosis: longitudinal prospective study.  British Medical Journal 325 (2002): 1212-1213.

Geller, B. et al.  Four-year prospective outcome and natural history of mania in children with a prepubertal and early adolescent bipolar disorder phenotype.”  Arch Gen Psychiatry/61, May 2004 (459-467).

Henquet C, et al.  Prospective cohort study of cannabis use, predisposition for psychosis, and psychotic symptoms in young people.  British Journal of Psychiatry 2005 January 1; 330(7481): 11. (http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=15574485)

High-Potency Marijuana Sending Teens to ER, Rehab.   L. A. Times 4/29/2004 (cited in Join Together Online:  http://www.jointogether.org/y/0,2521,570717,00.html)

Kalant, H.   Adverse effects of cannabis on health: an update of the literature since 1996.      Prog Neuropsychopharmacol Biol Psychiatry. 2004 Aug;28(5):849-63.

Marijuana Myths & Facts: The Truth Behind 10 Popular Misperceptions  (White House Office of National Drug Control Policy)      http://www.whitehousedrugpolicy.gov/publications/marijuana_myths_facts/

“Reefer Madness” is available free online at: http://www.archive.org/movies.

Rey JM, Martin A, Krabman P.  Is the party over? Cannabis and juvenile psychiatric disorder: the past 10 years. J Am Acad Child Adolesc Psychiatry. 2004 Oct;43(10):1194-205.

Steadman, H et al (1998). Violence by people discharged from acute psychiatric inpatient facilities and by others in the same neighborhoods. Archives of General Psychiatry, 55, 393-401. 

Sussman, N and Westreich, L.  Chronic Marijuana Use and the Treatment of Mentally Ill Patients.  Primary Psychiatry 2003; 10(9)  (http://www.primarypsychiatry.com/pdf/art_411.pdf).

van Os J, et al. Cannabis use and psychosis: a longitudinal population-based study. Am J Epidemiol 2002;156: 319-27. [PubMed]

Wilcox HC, Anthony JC.  The development of suicide ideation and attempts: an epidemiologic study of first graders followed into young adulthood. Drug Alcohol Depend. 2004 Dec 7;76(Suppl):S53-S67.