Medical Cannabis and Addictions. October 2015 Charlie Reznikoff

Transcription

1 Medical Cannabis and Addictions October 2015 Charlie Reznikoff

2 Medical Cannabis Topics Is marijuana addictive? Is medical cannabis addictive? Will medical cannabis lead to increased adolescent use of recreational marijuana? How has the addictive stigma affected doctors attitudes about medical cannabis? Other important toxic effects of cannabis.

3 Is marijuana and/or medical cannabis addictive?

4 Diagnosing Marijuana use disorder A pattern of marijuana use over 12 months Mild: 2-3 symptoms Moderate: 4-5 symptoms Severe: >/=6 symptoms

5 Diagnosing marijuana use disorder 1. Larger amounts over longer periods of time than intended 2. Desire or unsuccessful efforts to cut down or control use 3. Time is spent to obtain, use or recover from the effects 4. Craving 5. Failure to fulfill role obligations at work, home or school 6. Persistent or recurrent social or interpersonal problems 7. Social, occupational, or recreational activities are given up 8. Recurrent use in situations that are physically dangerous 9. Use despite medical or psychiatric harm 10*.Tolerance 11*.Withdrawal *If the substance in question is a prescribed substance, these criteria are eliminated

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7 Cannabis ranked against other drugs of abuse Lancet 2007, 369, p

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10 What makes a drug addictive? Stimulates the nucleus accumbans And how powerfully it does so Rapid entry into the brain Inhaled > IV > snort > eat or drink Rapidly wearing off Tendency to cause physical dependency Causing withdrawal, tolerance Ability to improve mood

11 Crack cocaine smoked Stimulates the nucleus accumbans And how powerfully it does so Rapid entry into the brain Inhaled Rapidly wearing off Tendency to cause physical dependency Causing withdrawal, tolerence Ability to improve mood

12 Heroin IV Stimulates the nucleus accumbans And how powerfully it does so Rapid entry into the brain Inhaled > IV Rapidly wearing off Tendency to cause physical dependency Causing withdrawal, tolerance Ability to improve mood

13 Marijuana smoked Stimulates the nucleus accumbency And how powerfully it does so Rapid entry into the brain Inhaled Rapidly wearing off Tendency to cause physical dependency Causing withdrawal, tolerence Ability to improve mood

14 Likelihood of Addiction after experimentation Center for substance abuse, university of maryland, 2008

15 Is Marijuana Addictive? If <18 years, risk of addiction increased to 17%

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17 Self reported symptoms newly sober users compared to former users. Budney et al, J of Abnl Psyche 2003 vol 112 #3 p393

18 Cannabis withdrawal: Mild, not life threatening, irritability, poor sleep, poor appetite, restlessness Requires no treatment, only education and reassurance

19 Psychopharmacology, Nov2006, Vol. 188 Issue 4, p , 20p, 1 chart, 3

20 Distribution of THC in the Body (lipid soluble) Kreutz & Axelrod (1973)

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22 Inhaled cannabinoids are more addictive than eaten, but also more easily dosed to avoid side effects (see below)

23 Comment on addiction and diversion of dronabinol.

24 Comment on addiction and diversion of dronabinol. I ve never heard of it happening!

25 THC vs CBD CBD may offset addictive properties of THC

26 Conclusion: Medical cannabis might cause or feed addiction in some who use it. I would consider it a mild to moderate side effect.

27 So it is addictive in some. Why care? Docs are worried about the use of an addictive drug: Interfering with other medical care compliance Replacing more standard medical cares Causing harm to patient, family, community Dominating or distracting the medical visit

28 Are medical cannabis laws bad public policy that will increase adolescent marijuana use?

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31 Why would a young person try something new? Acceptability Availability Perceived safety

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36 Strict laws do not align with low use

37 What about the gateway effect?

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39 What about the gateway effect? Liberalizing marijuana law will uncouple marijuana use from other, harder drugs, and will close the gateway to other drugs Liberalizing marijuana law will lead to an increase in youth using marijuana, altering their brains in a way to make them vulnerable to other harder drugs, opening the gateway

40 Physician s concerns about medical cannabis for pain 87 primary care providers responded to a three question survey

41 Years lived with disability

42 Patients chronically medicating pain symptoms with intoxicants Pain Anxiety Withdrawal

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46 Survey conclusions Mixed opinions on intractable pain Lack of medical knowledge about cannabis is common High concern about how medical cannabis would affect the providers workday

47 Physician concerns Practicing medicine outside the evidence base norms, conventional pharmacies Recreating the opioid-for-pain epidemic Challenging conversation, demanding patients Paperwork and red tap Time and energy to learn something new Personal opinions about marijuana

48 Other important toxic effects of (medical) cannabis

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50 Active Placebo Set & Setting

51 Cannabis dilates blood vessels

52 lightheadedness & increase in resting heart rate with THC use

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55 Marijuana stimulates appetite Alcohol Carbos American Journal of Cardiology : p478

56 Kaiser study: 62,000 patients no association with marijuana and heart attacks or strokes

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60 Work place accidents associated with cannabis use Macdonald S, Hall W, Roman P, Stockwell T, Coghlan M, Nesvaag S. Testing for cannabis in the work-place: a review of the evidence. Addiction. 2010;105:

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62 New Zealand Dunedin Study >1000 cohort studied over 38 years Updated summer 2012 Neuropsych declines across the board in MJ users Age and dose dependent Mental health Verbal IQ Academic achievement and job satisfaction

63 Adolescents who used marijuana regularly were significantly less likely than their nonusing peers to finish high school or obtain a degree. They also had a much higher chance of later developing dependence, using other drugs, and attempting suicide

64 Marijuana and Psychosis Worsening of preexisting schizophrenia Increased psychiatric hospitalizations Acute reversible psychotic reaction Increased likelihood of eventual schizophrenia Acute irreversible psychotic reaction Psychotic break, Schizophrenia Zammit brit journal of psyche nov (5) p357 D souza, int. review of neurobiology 2007 (78) p289 Moore et al. LANCET July 28, 2007 P.319

65 Cannabis and psychosis 24% new psychosis cases linked to thc consumption BBC news 16, feb 2015

66 Mental Illness and Marijuana use

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70 Conclusions about Medical Cannabis THC containing drugs affect the brain s pleasure center and can cause addiction Medical THC has low-medium risk of addiction Unknown public health effect on adolescents Physicians are not ready for medical cannabis There are many important side effects of cannabinoids aside from addiction

71 Other conclusions Some will get addicted to medical cannabis Driving work and parenting may be affected by medical cannabis Mood, psychotic disorders and brain development is affected cannabis Medical cannabis is NOT more toxic than many commonly used medications Docs have a lot to learn about medical cannabis!

72 Thank you! Questions?