US Dept of Justice Position. What we WILL cover. State Statutes. State Statutes 10/2/2014. What we WON T cover Pro s & Con s of legalizing:

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1 Medical Marijuana & the Workplace Update Mark Upfal, MD, MPH Corporate Medical Director Detroit Medical Center DMC Occupational Health Services Associate Professor Wayne State University US Dept of Justice Position Marijuana is a dangerous, addictive drug that poses significant health threats to users. Marijuana has no medical value that can't be met more effectively by legal drugs. Michigan Occupational & Environmental Medicine Association October 17, 2014 What we WON T cover Pro s & Con s of legalizing: Medical Marijuana Recreational Marijuana What we WILL cover Medical Marijuana Statutes Types of Cannabinoid Drugs Therapeutic & Adverse Effects Impairment Fitness for Duty & Policy Implications Drug Testing State Statutes Legal recreational use in 2 states Legal medical use in 23 states & D.C. No state requires employer to tolerate OTJ use CA, MI, OR & WA courts upheld firing MMJ users w/ + UDS State Statutes AZ, CT, DE, IL, ME, MN & RI prohibit discrim on basis of being an MMJ pt AZ, DE, IL & MN prohibit discrim on basis of + UDS for THC (unless used or impaired on job) NM Court of Appeals (8/29/14) supports lower court finding that WC must reimburse MMJ costs NM Supreme Court to rule 1

2 Joseph Casias Battle Creek Walmart Employee x 5 yrs 2008 Associate of the Year Sinus/brain cancer patient x 10 yrs Fired after pos UDS Mich Supreme Court ruled in favor of Walmart Coats v. Dish Network Quadriplegic MMJ qhs treats painful leg spasms enabling sleep No evidence of job impairment Fired for + random UDS CO Supreme Court to hear case Colorado CO Supreme Court to rule on whether employer can discriminate based on Off-Duty Recreational Use ADA ADA offers no protections on the basis of MMJ use (illegal under federal law) However, be cautious not to discrim against the underlying disability Michigan Medical Marihuana Act Approved by voters 11/4/2008 Qualifying Diseases Cancer HIV; AIDS Glaucoma Hepatitis C Amyotrophic Lateral Sclerosis (ALS) Crohn s Disease Alzheimer s with agitation Nail Patella Syndrome PTSD (added March, 2014) 2

3 Qualifying Symptoms Cachexia (wasting syndrome) Severe Nausea Severe & Chronic Pain Severe or Persistent Muscle Spasms (e.g. MS) Seizures (e.g. epilepsy) Bona fide physician-patient relationship Review relevant medical records & complete a full, in-person assessment Maintain acceptable medical records Reasonable expectation of follow-up care to monitor treatment Notify PCP if patient permits Cannabinoid - Forms Herbal marijuana Pills Mouth spray Herbal Marijuana >4,000 years use for both euphoric & therapeutic effects Used in 2737 BC by Chinese Emperor Shen Neng > 400 substances & > 60 cannabinoids Smoking rapid delivery mood enhancement 9 min vs. 1-5 hrs Herbal Marijuana Rapid onset allows for self-titration when smoked However, studies unclear on whether subjects actually self-titrate vs. smoke to max effect THC content since 1980s from ave ~3% to ~12% in 2012 Herbal Marijuana - Edibles Candies, pastries, oil emulsions Longer duration, slower onset make titration difficult Variable outcomes depending on product concentration, absorption & indiv variation Some forms can be quite potent with surprise outcomes Most MJ related ED visits involve edibles 3

4 Herbal Marijuana Broader range of therapeutic compounds (as well as toxics) vs. pharmaceutical agents Some cannabinoids are psychoactive (THC, THC-OH); some are not (e.g. CBD, THC-V) Some strains are cultivated for high CBD/low THC content to minimize psychoactive effects ( Charlotte s Web ) Herbal Marijuana DEA Schedule I (like heroin, LSD no acceptable medical use; cannot prescribe per FDA) AMA recommends changing to Sched II (Nov 09) Remains illegal under federal law, even where legal under state law Generally not enforced when legal per state law Effects not correlated w/ absorbed dose, or blood or urine levels Inter-subject variability of effects Tachyphylaxis (rapid tolerance) Prior use patterns; expectations Interactions with other drugs Urine excretion highly variable THC metabolites -9-THC (main psychoactive ingredient) Metabolized to 11-OH-THC (psychoactive) Then to COOH-THC (not psychoactive; detected in UDS) THC Pill Form Liver metabolism Slower Onset; Longer Duration More difficult to use when nauseated Pure cannabinoid form Does not contain the additional cannabinoids in herbal marijuana Expensive Marinol (dronabinol) Synthetic 9 THC DEA Schedule III (lower abuse potential like Tyl #3) Ṫ po bid x 30d = $715 4

5 Cesamet (nabilone) Synthetic compound similar to 9- THC Used for CA chemo nausea & adjunct in neuropathic pain DEA schedule II (like cocaine; methamphetamine) Ṫ po bid x 30d = $2,010 Sativex (nabiximols): Oromucosal spray Canada & UK (not US) Herbal cannabis extract 1:1 THC:CBD Rapid Onset; Shorter Duration MS neuropathic pain, spasticity & overactive bladder Cancer pain (±)-trans-3-(1,1-dimethylheptyl)-6,6a,7,8,10,10a-hexahydro-1- hydroxy-6-6-dimethyl-9h-dibenzo[b,d]pyran-9-one Cannador - Oral Capsule Therapeutic & Adverse Effects Germany Herbal cannabis extract 2:1 THC:CBD Used for Muscle stiffness, spasms & pain in MS Anorexia/Cachexia in cancer Post-op pain mgmt Research on MMJ Few quality research studies NAS IOM Scientific Review request of White House ONDCP Center for Medicinal Cannabis Research, U-C, San Diego Research Limitations Funding Access to drug Small study pop ns Placebo easy to distinguish Volunteer subjects may differ from gen. pop n & may have efficacy expectations Subjectivity of some research endpoints 5

6 Mechanism of Action: Endocannabinoid receptors Discovered early 1990s Receptors in brain & body to wh/ cannabinoids attach & exert multi-system effects Nausea Pain Hunger Metabolism Anxiety Immune function & inflammation CB 1 Receptors Inhibit presynaptic release of various neurotranmitters Limbic system (mood) Hippocampus (memory) Basal ganglia Cerebellum Absence in medulla no respiratory depression CB 1 Receptors Pleasure Memory Concentration Sensory & time perception Coordinated movement CB 2 Receptors GI system Immune system, esp. spleen, leukocytes & tonsils Believed to reduce inflammation Vanilloid (capsaicin) receptors Found on sensory nerves Mediate nociception (pain perception) Capsaicin chili pepper ingredient Has analgesic properties by desensitizing the receptors Endocannabinoids also attach to these receptors & may have similar effect Cannabinoids Endocannabinoids Anandamide (Arachidonyl ethanolamide) 2-AG (2-Arachidonyl glycerol) Phytocannabinoids 9 -THC Cannabidiol (CBD) Nabiximols (Sativex ) (1:1 THC:CBD mouth spray) Synthetic Cannabinoids Nabilone (Cesamet ) 6

7 Endocannabinoids Exogenous Cannabinoids Derivatives of arachodonic acid (unlike phytocannabinoids, which are structurally different) Anandamide Most important (of 5 identified) (ananda = sanskrit for bliss ; N-arachidonoyl ethanolamide) -9 THC primary psychoactive agent binds CB 1 & CB 2 receptors about equally 11-OH-THC psychoactive 11-COOH-THC - Non-psychoactive; UDS detection Endocannabinoid Antagonists Rimonabant Selective CB 1 antagonist Effective e drug for obesity, substance abuse & smoking cessation Rejected by FDA due to severe depression & suicidality THC acute biological effects Effects on psyche - considerable individual variation Pleasant, relaxing mood for most users Anxiety or even panic for some Impaired concentration, memory, time perception Conjunctival injection, dry mouth, pupillary constriction Intraocular pressure (CB 1 effect) Analgesic, esp. for neuropathic pain THC acute biological effects Appetite THC GI motility & delays gastric emptying Leptin acts on hypothalamus Satiety Leptin endocannabinoids in animals Tachycardia; orthostatic hypotension Vagal inhibition via acetylcholine presynaptic CB 1 receptors Bronchodilitation Cannabinoids & neuroprotection Endocannabinoids are released in brain hypoxia, reducing resulting glutamate toxicity Anandamide & 2-AG admin to animals with TBI reduced brain injury THC neuroprotective in rats given neurotoxic agent, ouabain 7

8 Cannabinoids & immunity Effects on cellular & humoral immunity are complex Clinical relevance unclear MS, Crohn s, Arthritis research needed Antiviral actions? Cannabidiol (CBD) Mode of action not well understood; Evidence it may be: Sedating Anti-epileptic il Anti-emetic Anti-inflammatory Neuroprotective Antagonistic to psychotropic effects of THC Self-medication common for: Chronic pain MS Depression Arthritis Neuropathy CA chemotherapy HIV patients with nausea 3X more likely to comply with ART MMJ Efficacy best established for: Cachexia (Cancer; AIDS) appetite stimulation Severe nausea/vomiting (e.g. Chemotherapy) similar to phenothiazines Neuropathic pain & spasticity MS, Spinal cord/nerve tract trauma, diabetic neuropathy, HIV neuropathy Recent studies & observations suggest value for: Adjunct for pain to use of opiates Agitation g in Alzheimer patients Impact of MMJ on Opiate OD Study compared opioid OD mortality in states with & w/o MMJ laws 24.8% mean annual opioid OD mortality rate (p=0.003) 003) OD rate strengthened over time since implementation of law Bachhuber MA, et al, Medical Cannabis Laws and Opioid Analgesic Overdose Mortality in the United States, , JAMA Intern Med, Aug

9 Impact of MMJ on Opiate OD Interesting, but more research required Suggests MMJ might reduce Opioid use either as a substitute or an adjuvant Does not support the gateway theory, which might be expected to increase Opioid mortality Recent studies & observations suggest value for: Selected cases of epilepsy 7 yo Charlotte Figi Severe myoclonic seizures of infancy (Dravet Syndrome) 300 seizures/wk; DNR status Low THC/high CBD strain of marijuana 2-3 seizures/mo Glaucoma IOP ~ 25-30% Value unproven Should NOT replace effective treatments High doses admin frequently (q 3-4 hrs) Research into non-psychotropic cannabinoids may be worthwhile Other Touted Indications Inadequate research data May be beneficial, but anecdotally supported Use for mental health disorders? PTSD ADHD Depression Anxiety disorders Bipolar disorder Paranoia Adverse Effects While less severe vs. alcohol, tobacco, vicodin & cocaine, MJ has toxic effects: Psychoactive effects Respiratory effects Toxins similar to tobacco Lower exposure doses vs. tobacco Usually smoked unfiltered Short-term Adverse Effects Respiratory irritation; cough Similar to smoking other dried plant mat l Sedation, dizziness Anxiety Tachycardia; hypotension Cognitive effects Memory, attention, reaction time Safety concerns 9

10 Short-term Adverse Effects Dose dependent Readily reversible No established lethal dose Long Term Adverse Effects Cumulative & dose dependent Amount, freq & duration of use Respiratory hazard Exacerbation of COPD & asthma; Lung CA? JAMA (2012) 20 yr longitudinal study (n=5,115): No adverse respiratory effect (FEV1 & 7 joint-yrs. Long Term Adverse Effects Gateway drug? Postulated since 1930 s Remains controversial Association w/ hard drug use Not shown to be causative Most MJ users do not use hard drugs Dependence Tolerance May be due to downregulation and/or desensitization of endocannabinoid receptors Develops for most THC effects Cardiovascular, Psychomotor, Analgesia, etc. Psychological & cognitive effects Drug Dependence DRUG CATEGORY % DEPENDENT Tobacco 32 Heroin 23 Drug Dependence Cannabis withdrawal relatively mild vs. opiates, tobacco, EtOH & benzos More similar to caffeine Cocaine 17 Alcohol 15 Marijuana 9 10

11 Cannabis & Adolescence Assoc w/ schizophrenia & other mental health disorders Chronic use may risk of schizophrenia in vulnerable individuals High doses can trigger acute psychotic episodes in those w/ underlying psychotic conditions response to neuroleptic drugs & poor clinical course among schizophrenics Is the Association Causative? Confounded by genetic factors? Confounded by use of other drugs? Do schizophrenics self-medicate w/ cannabis? Cannabis & Adolescence Also assoc w/ poorer educational outcomes & social relationships Causality unknown Innate differences btwn those who do or don t smoke MJ? Neurotoxic effect of MJ? Schizophrenia Prevalence ~ 7 per 1,000 in US ~ 14 per 1,000 in cannabis users ~ 1 per 10 in those w/ schizophrenic 1 st degree relative If multiplicative, risk for cannabis users w/ genetic predisposition may be 1 in 5! Impairment Impairment Section 7(b) Prohibitions while under the influence Operating a vehicle (car, boat, plane) Performing tasks if negligent or professional malpractice 11

12 Impairment Operating a vehicle (car, boat, plane) Safety-sensitive work Motor tasks Cognitive tasks Impairment Marijuana cognitive, behavioral & motor effects highly variable Some individuals mood enhancement w/o measurable impairment Others signif impairment w/ same dose Task Complexity Simple, routine, well learned tasks not measurably impaired Brain scans reveal greater use of brain is required to perform simple tasks recruitment of neuronal pathways may compensate More impairment w/ complex & unexpected tasks Driving - Marijuana Dose dependent effect Impairs performance on driving simulation up to 3 hrs car handling performance Slower reaction time Impairs time & distance estimation Driving - Marijuana Drivers tend to overestimate impairment & attempt to compensate Driving slower following distance Less likely to pass Routine driving skills not significantly impaired, but response to emergencies and unexpected events is impaired Driving - EtOH Alcohol & other drugs more dramatic effect on performance, depending on dosage and individual tolerance Alcohol l also inhibitions limiting iti user s ability to compensate for the impairment Drivers tend to underestimate impairment 12

13 2007 US Nat l Roadside Study Random stops of ~11,000 drivers in 300 locations Voluntary, anonymous participation Breath alcohol (86%) Saliva drug (71%) Blood drug (39%) Results 1.3% Methamphetamine + 2.2% EtOH > 0.08 g/dl 3.9% Cocaine + 8.6% THC + DUI (alcohol) since 1973 Culpability studies 8.0% 7.0% 6.0% 5.0% 4.0% 3.0% 2.0% 1.0% 0.0% % of weekend nighttime drivers w/ BAC > 0.08 g/dl Not yet established that marijuana users are at higher risk of crashes Evidence inconclusive; studies are inconsistent Many study limitations, incl. distinguishing current from prior use No biomeasure can determine impairment Unknown if accident risk in occ l users compared w/ chronic, tolerant users Cannabis & Driving Summary Fitness for Work Cannabis impairs driving, esp. challenging driving situations & accident avoidance Effect depends on dose, timing of use & individual tolerance Alcohol s effects tend to be more dramatic 13

14 Can the employee work? MMJ use prohibited by federally mandated drug testing rules Others subject to state laws, employer s policy & collective bargaining agreements Safety-Sensitive Work No one should be allowed to perform safety-sensitive work while under the influence of cannabis (or any other substance illicit, prescribed or OTC) Where does the employer have discretion? Non safety sensitive work Off the job use Medical vs. recreational use Workplace Impact Research inadequate to measure impact of off-duty marijuana use on safety, productivity, absenteeism, presenteeism, etc. Effect on driving & other task performance typically abates w/in ~3-4 hrs Workplace Policy Implications Section 7(c) No requirement that an employer accommodate workplace use in Michigan Fitness for Duty Considerations: When is marijuana used? On the Job On weekends; evenings During LOA 14

15 Fitness for Duty Considerations: When is marijuana used? Consider timing as w/ OTC & prescription meds Vicodin Benadryl Cannot establish timing w/ UDS Fitness for Duty Considerations: Nature of Work? Safety Sensitive Work Driving Construction/Maintenance/Power Equipment Public Safety Positions Medical Decision Making Non-Safety Sensitive Work Monitor Productivity & Quality of Work Field Sobriety Testing Used extensively for EtOH Not validated for cannabis Effects on motor, coord, speech & balance may differ from EtOH Scleral hyperemia & tachycardia freq seen w/ cannabis, but very non-specific Typical odor of marijuana a clear indicator Drug Tests for THC Herbal Marijuana Marinol Sativex Cesamet NOT detected K2, Spice, Herbal Incense NOT detected Marinol vs. Herbal Marijuana Tetrahydrocannabivarin (THCV) not in Marinol Urine & Hair Testing + UDS impairment or same day use Chronic users + UDS up to mo. or more Hair tests miss recent use & can be + for > 3 mos 15

16 Blood Testing Whole blood for post-mortem Plasma for living individuals Whole : Plasma roughly 1 : 2 5 ng/ml whole = 10 ng/ml plasma Note that post-mortem there is little to no metabolism, so the level represents the level at the time of death Which may or may not be the time of accident Living specimens may be delayed from time impairment is suspected Blood Testing THC-COOH persists for extended period, esp. in chronic users THC-COOH cannot establish current use or impairment THC and THC-OH do correlate with very recent use Blood Testing: THC or THC-OH Per se levels are being applied in some states (e.g. 5 ng/ml) 7-10 ng/ml 0.08% BAC 4 ng/ml 0.04% BAC Secondhand smoke can peak up to several ng/ml Freq users may 2+ ng/ml up to 48 hrs Plasma Levels Rough Guide 0 2 ng/ml 2 5 ng/ml 5+ ng/ml Casual user Cannot establish impairment Likely impaired Likely impaired Chronic user Cannot establish impairment Cannot establish impairment Likely impaired 16