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Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30. Published in final edited form as: Psychol Addict Behav. 2015 September ; 29(3): 639–642. doi:10.1037/adb0000111.
Variability in Medical Marijuana Laws in the United States Jessica Bestrashniy and Department of Mathematics, St. Olaf College Ken C. Winters Department of Psychiatry, University of Minnesota
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Abstract Marijuana use and its distribution raise several complex health, social and legal issues in the United States. Marijuana is prohibited in only 23 states and pro-marijuana laws are likely to be introduced in these states in the future. Increased access to and legalization of medical marijuana may have an impact on recreational marijuana use and perception through increased availability and decreased restrictiveness around the drug. The authors undertook an analysis to characterize the policy features of medical marijuana legislation, including an emphasis on the types of medical conditions that are included in medical marijuana laws. A high degree of variability in terms of allowable medical conditions, limits on cultivation and possession, and restrictiveness of policies was discovered. Further research is needed to determine if this variability impacts recreational use in those states.
Author Manuscript
Keywords medical marijuana; laws
Introduction
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While not strictly an illegal drug like many other illicit or Schedule I drugs such as methamphetamine or cocaine, marijuana is the most commonly used among them in the United States. Approximately 12% of individuals 12 years of age or older reported using this drug in 2103, and rates are the highest at the younger ages (Center for Behavioral Health Statistics and Quality, 2013). Moreover, more Americans now perceive that marijuana is harmless than view it as harmful (Pew Research Center, 2013), and it is becoming a popular notion that it should not be regulated or considered illegal. The legal trajectory of marijuana has been a dynamic one, from being first classified as a Schedule I substance in the Controlled Substances Act of 1970 and further criminalized by the Reagan administration’s War On Drugs in the 1980’s, to California being the first state to allow medical marijuana in 1996. Despite the continuation of the federal prohibition of any use of marijuana products (a synthetic version, Marinol, is permissible for limited medical conditions), the use of both recreational and medicinal marijuana has been entirely legalized in the states of Colorado,
Send correspondence to Jessica Bestrashniy, Department of Mathematics, Statistics, and Computer Science, St. Olaf College, RegentsMath 303, 1520 Saint Olaf Avenue, Northfield, MN 55057 [email protected].
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Washington, Alaska and Oregon and the District of Columbia. Twenty-three other states have medical use or decriminalization laws, or both (see www.learnaboutsam.org), and it is anticipated that the next few years will bring additional changes to the legal marijuana landscape.
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As policy shifts toward medicalization and legalization of marijuana, it is reasonable to expect that prevalence rates and resulting health consequences will increase. Use of marijuana has been linked to negative health effects, but the evidence varies as a function of age of user, whether use is occasional or heavy, and health domain, and is largely correlational in nature (Volkow, Baler, Compton & Weiss, 2014). Nonetheless, the summary by Volkow and colleagues (2014) of the literature identified four areas of health with strong links between marijuana use and adverse effects: addiction to marijuana and other substances, diminished life achievement, motor vehicle accidents, and symptoms of chronic bronchitis. These effects are greater for individuals who initiate use during adolescence and have heavy and long-term patterns of use.
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In contrast to these reports of possible negative health consequences, there are credible reports by individuals suffering from chronic pain and a variety of chronic illnesses (seizure disorders, cancer, glaucoma, multiple sclerosis, AIDS wasting syndrome) that smoking marijuana improved their conditions when standard treatments did not (e.g., Meinck, Schonle, & Conrad, 1989). Also, among patients recovering from opiate addiction, those who smoked marijuana experienced less severe withdrawal symptoms (Scavone, Sterling, Weinstein & Von Bockstaele, 2013). The 1999 report by the Institute of Medicine concluded that among the more than 400 known elements and compounds within a typical marijuana plant, some of them are associated with genuine medicinal effects for the treatment of pain and other medical symptoms (Watson, Benson & Joy, 2000).
Author Manuscript
As laws and attitudes regarding the permissiveness of marijuana use continue to shift, it is germane to reflect and summarize the current state of the regulations surrounding this drug. Individual states are exercising freedom with respect to establishing the context under which possession and use are legal, and there is a great deal of variability as to which medical conditions are eligible for medical marijuana as well as the particular controls and boundaries established by these laws. For example, some medical marijuana states permit an individual to grow their own plants whereas others do not; some states have a limited list of medical conditions and some are quite liberal in this area. It is important to characterize this variability among states in order to facilitate evaluations as to which regulations protect the patient who is legally using marijuana and which are associated with changes in use patterns in the general population. One of the primary concerns with allowing medical marijuana in the first place is that dispensaries and generous relatives might serve as new reservoirs via which individuals might obtain marijuana illegally, thus increasing opportunities for illicit use (Lynne-Landsman, Livingston, & Wagenaar, 2013). Given that a characterization of medical marijuana laws has not yet been undertaken, the authors sought to identify key distinguishing features of medical marijuana policies across states and to classify them with respect to degree of permissiveness. A greater understanding
Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30.
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of current polices will help to inform future policies and serve as a means by which the strength of existing policies can be assessed.
Materials and Methods
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Data from the statues and bills that established medical marijuana in that state (or DC) was abstracted. Two sources were utilized: http://www.ncsl.org/research/health/state-medicalmarijuana-laws.aspx and http://medicalmarijuana.procon.org/view.resource.php? resourceID=000881#Minnesota. A single reviewer (senior author) carefully read each piece of legislation and recorded information onto an abstraction sheet. Abstracted data were confirmed via an alternative method such as a state-specific medical marijuana website to ensure correct interpretation of the legislation. A single reviewer completed each abstraction twice with a one-week washout period between abstractions. The second author (Winters) independently reviewed the data on individual state legislations (based on at ncsl.org); no inconsistencies with the senior author’s description of legislation were found. For each state, information was collected on a number of quantitative and qualitative factors regarding their marijuana policy (medical only or both medical and recreational). The following variables were recorded and are included in Table 1: how the bill was passed (popular vote, by state legislature), the percentage of the vote associated with the passage of the bill, the year of passage, whether registration is mandatory, and the number of medical conditions that qualified for medical marijuana intervention.
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Also, various data were collected and used to calculate these three indices - permissiveness of cultivation, permissiveness of possession, and overall restrictiveness (indices shown in Table 1). The cultivation index was derived from the number of allowed mature and immature plants per state. A state can have a maximum of six points: 0 for no cultivation is permitted, 1 point for cultivation of < 5 immature plants, 2 points for cultivation of 5 -10 immature plants, and 3 points for cultivation of more than 10 immature plants Three additional points were assigned for states that also permitted cultivation of mature plants.
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The possession index was derived from both possession amount (in ounces) and possession time (how many days’ worth can be obtained at once). Scoring for possession amount was as follows: 0 points for states that did not allow possession of smokeable marijuana; 1 point was assigned for an ounce or less, 2 points for more than an ounce but less than 6 ounces, and 3 points were for states allowing possession of 6 ounces or more. Possession time scoring was as follows: 1 point was assigned for states allowing the purchase of supplies of 15 days or fewer, 2 points were assigned for states that allowed supplies of sixteen to 59 days, and 3 points were given to states that did not restrict how often an individual could obtain more marijuana. For both of these indices, higher scores indicate higher permissiveness. The restrictiveness index combined possession and cultivation (in tertiles), and the number of conditions accepted by that state where 1 point was added to states allowing more conditions than the median number of conditions. For this index, higher scores indicate
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greater overall restrictiveness. Some states had revisions or clarifications to their statutes; revisions rather than the original statute were included. Finally, a word cloud was prepared that represents the frequency with which each state listed specific medical conditions that were permissible for medical marijuana intervention (also obtained from the two sources noted above). Word sizes are directly proportional to the proportion of states that accept a particular condition.
Results
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Table 1 provides a summary of legislation features for the 23 states and Washington, DC that have passed medical marijuana laws. The earliest was California in 1996, and the most recent were Minnesota, New York, and Maryland in 2014. Of those, 11 (45.8%) medical marijuana policies were passed by popular vote as opposed to state legislatures (or counsel in the case of DC). Only one state congress with medical marijuana overrode a governor’s veto to pass the law (RI). Two states (MN and NY) do not allow smokeable marijuana. The cultivation index was highest in Alaska, California, Michigan, New Mexico, Oregon, Rhode Island, and Washington. The possession index was highest in California, Hawaii, New Mexico, Oregon, and Washington. Colorado and Oregon scored the highest on the restrictiveness index. Maryland, Massachusetts, Minnesota, and New York had low scores on all three indices. The number of conditions accepted ranged from six (WA) to 40 (IL). The mean number of conditions was 12.8 (SD = 6.8).
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Figure 1 depicts the frequency with which each state listed specific medical conditions were permissible for medical marijuana. The size of the word in the figure is directly proportional to the proportion of states who accept that condition. For example, cancer was listed in all states, hence it is large, whereas hepatitis C was listed in fewer states, and therefore it appears much smaller in the figure. Several conditions were consistently listed in most states, such as glaucoma and multiple sclerosis, but numerous conditions were limited to one or two states (e.g., anorexia or Arnold-Chiari malformation).
Discussion
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Data from states permitting medical marijuana was assessed to determine whether significant variability existed across states in regard to specific features of their marijuana policies. Whereas almost half of the states in the US now have laws permitting the use of marijuana for medical purposes, there is great variability in features among them. For example, states varied considerably in the number and types of conditions that are permitted to use medical marijuana; for example, Illinois permits marijuana for about seven times the number of conditions (40) permitted by Washington, the most restrictive state (6). Mental conditions such as PTSD and anorexia were not as common as terminal conditions such as ALS, or chronic conditions such as muscle spasms and migraines. There was also a considerable range in the restrictiveness index. This was due to states varying in terms of the amount/number of days’ supply and the number of plants that can be cultivated (if they can be cultivated at all). This index reflects the extent of autonomy allowed for the patient and caregiver. That is, the more a patient or caregiver is allowed to Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30.
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possess or cultivate themselves, the greater the flexibility in the administration of dosage. On the other hand, the restrictiveness index may impact the extent to which the drug is available to individuals in the household not prescribed to receive medical marijuana.
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The present analysis did not address whether states allowing medical marijuana are associated with different marijuana use patterns compared to states with no medical marijuana legislation. There are concerns that medical marijuana may become a recreational source for healthy individuals to obtain marijuana illegally. There are no consistent epidemiological data indicating that the prevalence of marijuana use has significantly increased in states after the first few years of enactment of medical marijuana laws (e.g., Lynne-Landsman et al., 2013). Two recent examinations of the link between medical marijuana laws and prevalence rates of marijuana use by adolescents reflect the complexity of the issue; one study showed no link (Hasin et al., 2015) and the other did show an association (Stolzenberg, D’Alessio, & Dariano, 2015). Whether these state and national trends continue as more time elapses remains an open question. Many important questions are yet to be answered in this increasingly important area of public health, health care, and policy. Most states allow cannabis to be cultivated and smoked for medical purposes, despite the potential health concerns of smoking. Alternatives to traditional smoked cannabis exist; these include Dronabinol (Marinol ®) and Nabilone (Cesamet ®). However, they have been shown to produce limited effectiveness in the treatment of nausea and vomiting caused by chemotherapy in people (Straus, 2000). Also, cannabis oils that contain high amounts of cannabidiol (CBD), the compound in cannabis with medical properties (Volkow et al., 2014), are being developed but clinical trials are needed to determine their effectiveness.
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The autonomy of each state’s legal bodies allow for a variety of policies to be put in place regarding both recreational and medical marijuana. There are several possible implications these laws could have in regards to uptake and use by non-patients. First, more permissive medical laws may make obtaining marijuana easier for individuals without a prescription. In addition, permissive medical marijuana laws may contribute to pro-marijuana attitudes, which may lead to greater marijuana use and a greater willingness to legalize marijuana for recreational use. Further research using the permissiveness indicators identified here could be used to disentangle the various roles these indicators may play in impacting marijuana attitudes and use for individuals with a recreational intent.
Acknowledgments Author Manuscript
This study was supported by grants DA017492 and DA035882 from the National Institute on Health to the second author.
References Hasin, DS.; Wall, M.; Keyes, KM.; Cerdá, M.; Schulenberg, J.; O’Malley, PM.; Galea, S.; Pacula, R.; Feng, T. Medical marijuana laws and adolescent marijuana use in the USA from 1991 to 2014: results from annual, repeated cross-sectional surveys. Lancet Psychiatry. Jun 16. 2015 published online, http://dx.doi.org/10.1016/S2215-0366(15)00217-5
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Lynne-Landsman SD, Livingston MD, Wagenaar AC. Effects of state medical marijuana laws on adolescent marijuana use. American Journal of Public Health. 2013; 103:1500–1506. [PubMed: 23763418] Meinck HM, Schonle PW, Conrad B. Effect of cannabinoids on spasticity and ataxia in multiple sclerosis. Journal of Neurology. 1989; 236:120–122. [PubMed: 2709054] Pew Research Center. General Social Survey, 1969–2013. Washington, DC: Pew Research Center; 2013. Scavone JL, Sterling RC, Weinstein SP, Von Bockstaele EJ. Impact of cannabis use during stabilization on methadone maintenance treatment. The American Journal on Addictions. 2013; 22:344–351. [PubMed: 23795873] Stolzenberg, L.; D’Alessio, SJ.; Dariano, D. The effect of medical marijuana laws on juvenile marijuana use. International Journal of Drug Policy. Jun 6. 2015 published online, http://dx.doi.org/ 10.1016/j.drugpo.2015.05.018 Straus SE. Immunoactive cannabinoids: Therapeutic prospects for marijuana constituents. Proceedings of the National Academy of Sciences. 2000; 97:9363–9364. Volkow ND, Baler RD, Compton WM, Weiss SRB. Adverse health. effects of marijuana use. The New England Journal of Medicine. 2014; 370:2219–2227. [PubMed: 24897085] Watson SJ, Benson JA, Joy JE. Marijuana and medicine: Assessing the science base. A summary of the 1999 Institute of Medicine report. Archives of General Psychiatry. 2000; 57:547–552. [PubMed: 10839332]
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Figure 1.
Word map of medical conditions permitted to use medical marijuana by state. Size of the word is directly related to the proportion of states who include that particular condition. Thus, larger words are more common across states and smaller words reflect conditions included in fewer states.
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Author Manuscript popular vote
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Summary measure of overall cultivation regarding home cultivation; higher scores mean greater cultivation is permitted; see text for details.
Does not allow smokeable marijuana.
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Overview of Medical Marijuana Policy Features and Policy Indices
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Summary measure of overall restrictiveness combines cultivation and possession scores, as well as number of conditions; higher scores mean greater restrictiveness; see text for details.
4
Summary measure of overall permissiveness regarding possession amount and frequency; higher scores mean greater possession is permitted; see text for details.
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Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30. Published in final edited form as: Psychol Addict Behav. 2015 September ; 29(3): 639–642. doi:10.1037/adb0000111.
Variability in Medical Marijuana Laws in the United States Jessica Bestrashniy and Department of Mathematics, St. Olaf College Ken C. Winters Department of Psychiatry, University of Minnesota
Author Manuscript
Abstract Marijuana use and its distribution raise several complex health, social and legal issues in the United States. Marijuana is prohibited in only 23 states and pro-marijuana laws are likely to be introduced in these states in the future. Increased access to and legalization of medical marijuana may have an impact on recreational marijuana use and perception through increased availability and decreased restrictiveness around the drug. The authors undertook an analysis to characterize the policy features of medical marijuana legislation, including an emphasis on the types of medical conditions that are included in medical marijuana laws. A high degree of variability in terms of allowable medical conditions, limits on cultivation and possession, and restrictiveness of policies was discovered. Further research is needed to determine if this variability impacts recreational use in those states.
Author Manuscript
Keywords medical marijuana; laws
Introduction
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While not strictly an illegal drug like many other illicit or Schedule I drugs such as methamphetamine or cocaine, marijuana is the most commonly used among them in the United States. Approximately 12% of individuals 12 years of age or older reported using this drug in 2103, and rates are the highest at the younger ages (Center for Behavioral Health Statistics and Quality, 2013). Moreover, more Americans now perceive that marijuana is harmless than view it as harmful (Pew Research Center, 2013), and it is becoming a popular notion that it should not be regulated or considered illegal. The legal trajectory of marijuana has been a dynamic one, from being first classified as a Schedule I substance in the Controlled Substances Act of 1970 and further criminalized by the Reagan administration’s War On Drugs in the 1980’s, to California being the first state to allow medical marijuana in 1996. Despite the continuation of the federal prohibition of any use of marijuana products (a synthetic version, Marinol, is permissible for limited medical conditions), the use of both recreational and medicinal marijuana has been entirely legalized in the states of Colorado,
Send correspondence to Jessica Bestrashniy, Department of Mathematics, Statistics, and Computer Science, St. Olaf College, RegentsMath 303, 1520 Saint Olaf Avenue, Northfield, MN 55057 [email protected].
Bestrashniy and Winters
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Washington, Alaska and Oregon and the District of Columbia. Twenty-three other states have medical use or decriminalization laws, or both (see www.learnaboutsam.org), and it is anticipated that the next few years will bring additional changes to the legal marijuana landscape.
Author Manuscript
As policy shifts toward medicalization and legalization of marijuana, it is reasonable to expect that prevalence rates and resulting health consequences will increase. Use of marijuana has been linked to negative health effects, but the evidence varies as a function of age of user, whether use is occasional or heavy, and health domain, and is largely correlational in nature (Volkow, Baler, Compton & Weiss, 2014). Nonetheless, the summary by Volkow and colleagues (2014) of the literature identified four areas of health with strong links between marijuana use and adverse effects: addiction to marijuana and other substances, diminished life achievement, motor vehicle accidents, and symptoms of chronic bronchitis. These effects are greater for individuals who initiate use during adolescence and have heavy and long-term patterns of use.
Author Manuscript
In contrast to these reports of possible negative health consequences, there are credible reports by individuals suffering from chronic pain and a variety of chronic illnesses (seizure disorders, cancer, glaucoma, multiple sclerosis, AIDS wasting syndrome) that smoking marijuana improved their conditions when standard treatments did not (e.g., Meinck, Schonle, & Conrad, 1989). Also, among patients recovering from opiate addiction, those who smoked marijuana experienced less severe withdrawal symptoms (Scavone, Sterling, Weinstein & Von Bockstaele, 2013). The 1999 report by the Institute of Medicine concluded that among the more than 400 known elements and compounds within a typical marijuana plant, some of them are associated with genuine medicinal effects for the treatment of pain and other medical symptoms (Watson, Benson & Joy, 2000).
Author Manuscript
As laws and attitudes regarding the permissiveness of marijuana use continue to shift, it is germane to reflect and summarize the current state of the regulations surrounding this drug. Individual states are exercising freedom with respect to establishing the context under which possession and use are legal, and there is a great deal of variability as to which medical conditions are eligible for medical marijuana as well as the particular controls and boundaries established by these laws. For example, some medical marijuana states permit an individual to grow their own plants whereas others do not; some states have a limited list of medical conditions and some are quite liberal in this area. It is important to characterize this variability among states in order to facilitate evaluations as to which regulations protect the patient who is legally using marijuana and which are associated with changes in use patterns in the general population. One of the primary concerns with allowing medical marijuana in the first place is that dispensaries and generous relatives might serve as new reservoirs via which individuals might obtain marijuana illegally, thus increasing opportunities for illicit use (Lynne-Landsman, Livingston, & Wagenaar, 2013). Given that a characterization of medical marijuana laws has not yet been undertaken, the authors sought to identify key distinguishing features of medical marijuana policies across states and to classify them with respect to degree of permissiveness. A greater understanding
Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30.
Bestrashniy and Winters
Page 3
Author Manuscript
of current polices will help to inform future policies and serve as a means by which the strength of existing policies can be assessed.
Materials and Methods
Author Manuscript
Data from the statues and bills that established medical marijuana in that state (or DC) was abstracted. Two sources were utilized: http://www.ncsl.org/research/health/state-medicalmarijuana-laws.aspx and http://medicalmarijuana.procon.org/view.resource.php? resourceID=000881#Minnesota. A single reviewer (senior author) carefully read each piece of legislation and recorded information onto an abstraction sheet. Abstracted data were confirmed via an alternative method such as a state-specific medical marijuana website to ensure correct interpretation of the legislation. A single reviewer completed each abstraction twice with a one-week washout period between abstractions. The second author (Winters) independently reviewed the data on individual state legislations (based on at ncsl.org); no inconsistencies with the senior author’s description of legislation were found. For each state, information was collected on a number of quantitative and qualitative factors regarding their marijuana policy (medical only or both medical and recreational). The following variables were recorded and are included in Table 1: how the bill was passed (popular vote, by state legislature), the percentage of the vote associated with the passage of the bill, the year of passage, whether registration is mandatory, and the number of medical conditions that qualified for medical marijuana intervention.
Author Manuscript
Also, various data were collected and used to calculate these three indices - permissiveness of cultivation, permissiveness of possession, and overall restrictiveness (indices shown in Table 1). The cultivation index was derived from the number of allowed mature and immature plants per state. A state can have a maximum of six points: 0 for no cultivation is permitted, 1 point for cultivation of < 5 immature plants, 2 points for cultivation of 5 -10 immature plants, and 3 points for cultivation of more than 10 immature plants Three additional points were assigned for states that also permitted cultivation of mature plants.
Author Manuscript
The possession index was derived from both possession amount (in ounces) and possession time (how many days’ worth can be obtained at once). Scoring for possession amount was as follows: 0 points for states that did not allow possession of smokeable marijuana; 1 point was assigned for an ounce or less, 2 points for more than an ounce but less than 6 ounces, and 3 points were for states allowing possession of 6 ounces or more. Possession time scoring was as follows: 1 point was assigned for states allowing the purchase of supplies of 15 days or fewer, 2 points were assigned for states that allowed supplies of sixteen to 59 days, and 3 points were given to states that did not restrict how often an individual could obtain more marijuana. For both of these indices, higher scores indicate higher permissiveness. The restrictiveness index combined possession and cultivation (in tertiles), and the number of conditions accepted by that state where 1 point was added to states allowing more conditions than the median number of conditions. For this index, higher scores indicate
Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30.
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greater overall restrictiveness. Some states had revisions or clarifications to their statutes; revisions rather than the original statute were included. Finally, a word cloud was prepared that represents the frequency with which each state listed specific medical conditions that were permissible for medical marijuana intervention (also obtained from the two sources noted above). Word sizes are directly proportional to the proportion of states that accept a particular condition.
Results
Author Manuscript
Table 1 provides a summary of legislation features for the 23 states and Washington, DC that have passed medical marijuana laws. The earliest was California in 1996, and the most recent were Minnesota, New York, and Maryland in 2014. Of those, 11 (45.8%) medical marijuana policies were passed by popular vote as opposed to state legislatures (or counsel in the case of DC). Only one state congress with medical marijuana overrode a governor’s veto to pass the law (RI). Two states (MN and NY) do not allow smokeable marijuana. The cultivation index was highest in Alaska, California, Michigan, New Mexico, Oregon, Rhode Island, and Washington. The possession index was highest in California, Hawaii, New Mexico, Oregon, and Washington. Colorado and Oregon scored the highest on the restrictiveness index. Maryland, Massachusetts, Minnesota, and New York had low scores on all three indices. The number of conditions accepted ranged from six (WA) to 40 (IL). The mean number of conditions was 12.8 (SD = 6.8).
Author Manuscript
Figure 1 depicts the frequency with which each state listed specific medical conditions were permissible for medical marijuana. The size of the word in the figure is directly proportional to the proportion of states who accept that condition. For example, cancer was listed in all states, hence it is large, whereas hepatitis C was listed in fewer states, and therefore it appears much smaller in the figure. Several conditions were consistently listed in most states, such as glaucoma and multiple sclerosis, but numerous conditions were limited to one or two states (e.g., anorexia or Arnold-Chiari malformation).
Discussion
Author Manuscript
Data from states permitting medical marijuana was assessed to determine whether significant variability existed across states in regard to specific features of their marijuana policies. Whereas almost half of the states in the US now have laws permitting the use of marijuana for medical purposes, there is great variability in features among them. For example, states varied considerably in the number and types of conditions that are permitted to use medical marijuana; for example, Illinois permits marijuana for about seven times the number of conditions (40) permitted by Washington, the most restrictive state (6). Mental conditions such as PTSD and anorexia were not as common as terminal conditions such as ALS, or chronic conditions such as muscle spasms and migraines. There was also a considerable range in the restrictiveness index. This was due to states varying in terms of the amount/number of days’ supply and the number of plants that can be cultivated (if they can be cultivated at all). This index reflects the extent of autonomy allowed for the patient and caregiver. That is, the more a patient or caregiver is allowed to Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30.
Bestrashniy and Winters
Page 5
Author Manuscript
possess or cultivate themselves, the greater the flexibility in the administration of dosage. On the other hand, the restrictiveness index may impact the extent to which the drug is available to individuals in the household not prescribed to receive medical marijuana.
Author Manuscript
The present analysis did not address whether states allowing medical marijuana are associated with different marijuana use patterns compared to states with no medical marijuana legislation. There are concerns that medical marijuana may become a recreational source for healthy individuals to obtain marijuana illegally. There are no consistent epidemiological data indicating that the prevalence of marijuana use has significantly increased in states after the first few years of enactment of medical marijuana laws (e.g., Lynne-Landsman et al., 2013). Two recent examinations of the link between medical marijuana laws and prevalence rates of marijuana use by adolescents reflect the complexity of the issue; one study showed no link (Hasin et al., 2015) and the other did show an association (Stolzenberg, D’Alessio, & Dariano, 2015). Whether these state and national trends continue as more time elapses remains an open question. Many important questions are yet to be answered in this increasingly important area of public health, health care, and policy. Most states allow cannabis to be cultivated and smoked for medical purposes, despite the potential health concerns of smoking. Alternatives to traditional smoked cannabis exist; these include Dronabinol (Marinol ®) and Nabilone (Cesamet ®). However, they have been shown to produce limited effectiveness in the treatment of nausea and vomiting caused by chemotherapy in people (Straus, 2000). Also, cannabis oils that contain high amounts of cannabidiol (CBD), the compound in cannabis with medical properties (Volkow et al., 2014), are being developed but clinical trials are needed to determine their effectiveness.
Author Manuscript
The autonomy of each state’s legal bodies allow for a variety of policies to be put in place regarding both recreational and medical marijuana. There are several possible implications these laws could have in regards to uptake and use by non-patients. First, more permissive medical laws may make obtaining marijuana easier for individuals without a prescription. In addition, permissive medical marijuana laws may contribute to pro-marijuana attitudes, which may lead to greater marijuana use and a greater willingness to legalize marijuana for recreational use. Further research using the permissiveness indicators identified here could be used to disentangle the various roles these indicators may play in impacting marijuana attitudes and use for individuals with a recreational intent.
Acknowledgments Author Manuscript
This study was supported by grants DA017492 and DA035882 from the National Institute on Health to the second author.
References Hasin, DS.; Wall, M.; Keyes, KM.; Cerdá, M.; Schulenberg, J.; O’Malley, PM.; Galea, S.; Pacula, R.; Feng, T. Medical marijuana laws and adolescent marijuana use in the USA from 1991 to 2014: results from annual, repeated cross-sectional surveys. Lancet Psychiatry. Jun 16. 2015 published online, http://dx.doi.org/10.1016/S2215-0366(15)00217-5
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Lynne-Landsman SD, Livingston MD, Wagenaar AC. Effects of state medical marijuana laws on adolescent marijuana use. American Journal of Public Health. 2013; 103:1500–1506. [PubMed: 23763418] Meinck HM, Schonle PW, Conrad B. Effect of cannabinoids on spasticity and ataxia in multiple sclerosis. Journal of Neurology. 1989; 236:120–122. [PubMed: 2709054] Pew Research Center. General Social Survey, 1969–2013. Washington, DC: Pew Research Center; 2013. Scavone JL, Sterling RC, Weinstein SP, Von Bockstaele EJ. Impact of cannabis use during stabilization on methadone maintenance treatment. The American Journal on Addictions. 2013; 22:344–351. [PubMed: 23795873] Stolzenberg, L.; D’Alessio, SJ.; Dariano, D. The effect of medical marijuana laws on juvenile marijuana use. International Journal of Drug Policy. Jun 6. 2015 published online, http://dx.doi.org/ 10.1016/j.drugpo.2015.05.018 Straus SE. Immunoactive cannabinoids: Therapeutic prospects for marijuana constituents. Proceedings of the National Academy of Sciences. 2000; 97:9363–9364. Volkow ND, Baler RD, Compton WM, Weiss SRB. Adverse health. effects of marijuana use. The New England Journal of Medicine. 2014; 370:2219–2227. [PubMed: 24897085] Watson SJ, Benson JA, Joy JE. Marijuana and medicine: Assessing the science base. A summary of the 1999 Institute of Medicine report. Archives of General Psychiatry. 2000; 57:547–552. [PubMed: 10839332]
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Figure 1.
Word map of medical conditions permitted to use medical marijuana by state. Size of the word is directly related to the proportion of states who include that particular condition. Thus, larger words are more common across states and smaller words reflect conditions included in fewer states.
Author Manuscript Author Manuscript Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30.
Author Manuscript
Author Manuscript popular vote
state legislature popular vote
state legislature state legislature
Medical
Medical
Medical
Medical
Medical
Medical
Medical
Medical
Medical
Medical
Medical
Medical
Medical
Both
Medical
Medical
Both
HI
IL
ME
MD
MA
MI
MN1
MT
NV
NH
NJ
NM
NY1
OR
RI
VT
WA
counsel
Psychol Addict Behav. Author manuscript; available in PMC 2015 September 30. 59.0
58.2
82.0
55.0
87.8
66.7
73.0
81.2
65.0
62.0
70.7
63.0
63.0
92.3
61.0
55.0
60.0
71.0
100.0
64.6
54.0
56.0
50.1
58.0
Passed By (%)
1998
2004
2005
1998
2014
2007
2010
2013
2000
2004
2014
2008
2012
2014
1999
2013
2000
2011
2010
2012
2000
1996
2010
1998
Year
6
7
13
11
10
19
17
19
10
13
11
16
9
7
8
40
11
12
9
11
11
14
15
9
# Conditions Accepted1
6
5
6
6
0
6
0
0
4
5
0
6
0
0
5
0
4
0
0
0
5
6
6
4
Cultivation Index2
7
6
6
7
2
7
4
6
5
5
2
6
2
3
5
5
7
5
6
6
6
7
5
4
Possession Index3
Summary measure of overall cultivation regarding home cultivation; higher scores mean greater cultivation is permitted; see text for details.
Does not allow smokeable marijuana.
2
1
none
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
voluntary
mandatory
mandatory
mandatory
mandatory
mandatory
mandatory
voluntary
mandatory
mandatory
Registration
Both = law permitting both medical and recreational use of marijuana.
popular vote
popular vote
state legislature
state legislature
state legislature
state legislature
popular vote
popular vote
state legislature
popular vote
popular vote
state legislature
state legislature
state legislature
Both
Medical
DE
state legislature
DC
Both
Medical
CT
Medical
CO
popular vote
Medical
AZ
CA
popular vote
popular vote
Medical
AK
Pass
Type
State
Author Manuscript
Overview of Medical Marijuana Policy Features and Policy Indices
3
1
3
4
1
2
2
3
2
2
2
3
1
1
3
3
2
2
3
2
4
3
3
1
Restrictiveness Index4
Author Manuscript
Table 1 Bestrashniy and Winters Page 8
Author Manuscript
Author Manuscript
Author Manuscript
Summary measure of overall restrictiveness combines cultivation and possession scores, as well as number of conditions; higher scores mean greater restrictiveness; see text for details.
4
Summary measure of overall permissiveness regarding possession amount and frequency; higher scores mean greater possession is permitted; see text for details.
Author Manuscript
3
Bestrashniy and Winters
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