Table 1 Brief summary of included studies

Aggarwal et al. 2009

To characterize chronic pain patients seeking medical cannabis treatment.

Quantitative: Retrospective chart review; recruitment via a regional pain clinic.

Washington State, USA.

2007–2008, study, access points for medical cannabis dispensing in urban centers were informally tolerated.

139 patients seeking treatment with medical cannabis.

Median 47 (18–84) years.

63% men.

Chronic pain:

82% myofascial pain syndrome

64% neuropathic pain

27% osteoarthritis.

The majority of patient records documented significant symptom alleviation.

Scholarship funding

*National Institute of General Medical Sciences of the NIH

*National Science Foundation

Aggarwal et al. (2013a & 2013b)

To present data from a dispensary-based survey of medical cannabis users.

Quantitative: Dispensary-based survey; recruitment through an medical cannabis dispensary.

Washington State, USA.

2007–2008, access points for medical cannabis dispensing in urban centers were informally tolerated.

37 chronically ill, qualified medical cannabis users.

41 (21–61) years.

65% men.

25% qualified with intractable pain.

51% used medical cannabis to reduce musculoskeletal pain.

59% of the participants reported that 3.4 grams of medical cannabis provided 97% pain relief for 65 h.

Scholarship funding

National Science Foundation Graduate Research Fellowship

Alexandre 2011

To identify patient’s expectations and experience of the enrollment to the Rhode Island medical cannabis program.

Qualitative: Semi-structured face-to-face interviews of patients enrolled in the medical cannabis program; recruitment via an information sheet distributed by the Rhode Island Patient Advocacy Coalition (RIPAC), supporting patients in the use of medical cannabis.

Rhode Island, USA.

2009–2010, legal MC use.

15 medical cannabis qualified users enrolled in the medical cannabis program.

23–60 years.

67% men.

Not reported for the study sample (67% of registered users diagnosed with chronic or debilitating disease or treatment, including chronic pain not related to cancer).

Reports of significant relief from pain.

No funding

Boehnke et al. 2016

To examine whether using medical cannabis for chronic pain changed individual patterns of opioid use.

Quantitative: Retrospective cross-sectional survey (online questionnaire carried out in collaboration with an medical cannabis dispensary)

Michigan, USA.

2013–2015

Legal MC use.

185 qualified medical cannabis users who completed the 2011 Fibromyalgia Survey Criteria.

18–75 years.

64% men.

Chronic pain.

Medical cannabis use was associated with a 64% decrease in opioid use, decreased number and side effects of medications, and an improved quality of life (45%).

N/A

Bonn-Miller et al. 2014

To describe population.

To examine association psychological & pain symptoms vs. medical cannabis use motives.

Quantitative: Cross-sectional questionnaires; recruitment via an medical cannabis dispensary.

California, USA.

Legal medical cannabis use.

217 qualified medical cannabis users receiving medical cannabis at dispensary.

41.2 ± 14.9 years.

73% men.

62% reported anxiety, 58% chronic pain, 49% stress, 48% insomnia, 45% depression, 30% appetite, 26% headaches, 22% nausea, 20% muscle spasms, 19% PTSD; less than 10% of the sample reported to use MC against cancer.

Regardless of condition, medical cannabis reported as moderately to mostly helpful.

(Mixed)

Research grant

VA Clinical Science Research and Development (CSR&D) Career Development Award-2

Local resource funding

San Francisco Patient and Resource Center

Bottorff et al. 2011

To describe perceived medical cannabis health effects.

Qualitative: Semi-structured, individual face-to-face or telephone interviews; recruitment through an online forum and through compassion centers.

British Columbia, Canada.

2007–2008, Marihuana Medical Access Regulations * but adults recruited from tolerated but illegal dispensaries.

23 self-reporting medical cannabis users.

45 (25–66) years.

43% men.

26% HIV/AIDS

22% fibromyalgia

17% arthritis

13% mood/anxiety disorders.

Reports of immediate effects and, for the first time in many years, participants “could manage life again.”

N/A

Bruce et al. 2018

To learn more on how medical cannabis is used by persons living with chronic conditions in tandem with or instead of prescription medications.

Qualitative: Semi-structured telephone interviews with open-ended questions; recruitment through flyers at medical cannabis dispensaries.

Illinois, USA.

Legal medical cannabis use.

30 qualified medical cannabis users.

44.6 ± 15.9 years.

63% men.

23% rheumatoid arthritis

20% Crohn’s disease

20% spinal cord injury/disease

13% cancer

10% severe fibromyalgia.

Medical cannabis perceived as acting more quickly, having longer effects, reducing potential harm versus opioids/narcotics.

Multiple benefits replacing a range of medications.

Fellowship grant

Provost’s Collaborative Research Fellowship, DePaul University

Brunt et al. 2014

To assess therapeutic satisfaction with pharmaceutical-grade cannabis.

To compare the subjective effects among the available strains.

Quantitative: Questionnaires; recruitment through pharmacies specialized in medical cannabis distribution.

The Netherlands.

2011-2012, pharmaceutical-grade cannabis distributed for medicinal purposes since 2003.

113 qualified medical cannabis users.

52.8 ± 12.3 years.

49% men.

53% chronic pain

23% multiple sclerosis; only 11% indicated to use medical cannabis against cancer.

86% (almost) always experienced therapeutic satisfaction, mainly pain alleviation.

Governmental funding

Ministry of Health, Welfare and Sport

Coomber et al. 2003

To report the experiences of medical cannabis users.

Qualitative: Semi structured interviews; recruitment via advertisements in newspapers, disabled people’s organizations or friends.

UK.

Illegal.

33 self-identified medical cannabis users.

44 (26–65) years.

58% men.

To relieve symptoms of chronic illness or disability:

42% multiple sclerosis

27% arthritic/rheumatoid complaints.

Medical cannabis perceived to be highly effective in treating symptoms, to complement existing medication, and to produce fewer unwanted effects.

N/A

Corroon et al. 2017

To survey cannabis users to determine whether they had intentionally substituted cannabis for prescription drugs.

Online survey, recruitment through social media, cannabis dispensaries and word of mouth.

83% of the USA (all 50 states represented) and over 42 countries represented.

2013–2016

Legality differed between the USA and countries.

Convenience sample of 2 774 cannabis users.

63% were under 36 y, 56% men.

60% identified themselves as medical cannabis users.

1040/2774 (37%) of respondents reported pain and/or intractable pain.

46% have substituted cannabis for prescription drugs.

Research grant

NIH NCCAM K01ATTA (Ste-Marie et al., 2016)

Cranford et al. 2016

To examine the prevalence and correlates of vaporization as a route of cannabis administration in medical cannabis users.

Quantitative: Data from the screening assessment; recruitment at medical cannabis clinics.

Michigan, USA.

2014–2015

Legal medical cannabis use.

1485 adults seeking medical cannabis certification either for the first time or as a renewal (66%).

45.1 ± 13 years.

57% men.

91% severe chronic pain

26% severe and persistent muscle spasms.

not reported

Research grant

National Institute on Drug Abuse (NIDA), National Institutes of Health

Crowell 2017

To ascertain the impact of medical cannabis on patients in New Jersey.

Quantitative: Survey with open-ended questions; recruitment via a non-profit organization dispensing medical cannabis

New Jersey, USA.

Legal medical cannabis use.

955 qualified medical cannabis users.

49.3 ± 13.6 (9–84) years.

51% men.

17 conditions were listed, including:

28% intractable skeletal spasticity

24% chronic/severe pain

16% multiple sclerosis

11% inflammatory bowel disease.

Improvement to general condition and quality of life. Decrease in pain, inflammation, nausea, intraocular pressure, spasms, seizure. Increase in appetite, mobility, mood and energy.

N/A

Degenhardt et al. 2015

To investigate patterns and correlates of cannabis use in people who had been prescribed opioids for chronic non-cancer pain.

Qualitative: Interview; recruitment via a database of pharmacies and chemists across Australia.

Australia.

Legal medical cannabis use.

242 patients prescribed opioids for chronic non-cancer pain which had used cannabis for pain.

48.7 ± 10.1 years.

62.5% men.

Chronic non-cancer pain, including:

84% back/neck problems

57% arthritis/rheumatism.

Among those using cannabis for pain, the average pain relief was 70% while the average pain relief from prescribed opioids was 50%.

Research grant

Australian National Health and Medical Research Council

Erkens et al. 2005

To characterize medical cannabis users, symptoms and conditions; daily use of medical cannabis.

Quantitative: Structured questionnaire; recruitment via pharmacies.

Netherlands.

2003–2004, since 2003, pharmaceutical-grade cannabis is distributed for medicinal purposes.

200 patients who filled a prescription for medical cannabis.

≥ 30 years.

33% men.

Cannabis mainly used for chronic pain (including rheumatic disease) and muscle cramp/stiffness.

Not reported

Governmental funding

Ministry of Health, Welfare and Sports, The Netherlands

Fanelli et al. 2017

To present the first snapshot of the Italian experience with cannabis use for chronic pain over the initial year of its use.

Quantitative: Retrospective case series (physician-filled case report form); recruitment via second-level pain clinics.

Pisa, Italy.

2015–2016, initial year of authorized medical cannabis use for chronic pain.

Legal medical cannabis use.

614 qualified medical cannabis users.

61.3 ± 15.3 years.

29% men.

91% chronic pain.

49% reported an improvement associated with the therapy.

15% stopped the treatment due to side effects (none of which were severe).

N/A

Gorter et al. 2005

To investigate indications for cannabis prescription.

To assess cannabis efficacy and side effects.

Quantitative: Standardized questionnaire; recruitment via questionnaires accompanying shipment of medical-grade cannabis directed to both patient and prescribing physician.

Netherlands.

1997–1999, before legalization but consumption of small amounts under certain conditions was then condoned.

107 patients receiving medical-grade cannabis on prescription.

Median 58 years.

45% men.

39% neurologic disorders

21% musculoskeletal/connective tissue disorders

14% malignant tumors and symptoms thereof.

64% reported good to excellent effect on their symptoms.

Generally mild side effects.

Non-governmental organization funding

Maripharm

Grella et al. 2014

To collect descriptive data on individuals using medical cannabis dispensaries.

Mixed

Focus groups and survey; recruitment via medical cannabis dispensaries. S

California, USA.

May–October 2012, legal medical cannabis use.

Users of medical cannabis dispensaries:

Focus groups: n = 30, 38 ± 12 (20–64) y, 70% men.

Survey: n = 182, 28.4 ± 5.3 y, 74% men.

Conditions most often cited (not mutually exclusive):

60% anxiety

56% insomnia/sleep problems

33% depression

42% chronic (non-cancer) pain.

Nearly all believed MC beneficial in treating their health problems.

Governmental funding

Los Angeles County Department of Public Health, Substance Abuse Prevention and Control Programs

Groten-hermen & Schnelle 2003

To investigate indications for cannabis prescription.

To assess cannabis efficacy and side effects.

Quantitative: Questionnaires; recruitment via an medical cannabis association.

German speech area of Europe.

2001: illegal use of natural cannabis products but THC could be prescribed.

143 participants with cannabis or THC experience.

Median 40.3 (16–87) years.

61% men.

28% neurological symptoms

25% painful conditions.

75% reported their conditions much improved by cannabis or THC.

73% reported no side effects.

N\A

Haroutounian et al. 2016

To determine the long-term effect of medical cannabis on pain and functional outcomes in participants with treatment resistant chronic pain.

Quantitative: Prospective, open-label, single-arm longitudinal study (questionnaires); recruitment via an ambulatory pain clinic.

Jerusalem, Israel.

2010–2013, legal medical cannabis use.

206 qualified medical cannabis users.

51.2 ± 15.4 years

62% men.

93% chronic non-cancer pain, including:

37% musculoskeletal pain

34% peripheral neuropathic pain

19% radicular low back pain.

Pain symptom score improved (P < 0.001) in association with improvement in physical function (P < 0.001).

9 (4%) discontinued treatment due to mild to moderate AEs; 2 (1%) discontinued to serious side effects (1 elevated liver transaminases, 1 elderly admitted to an Emergency Department in a confusional state).

Research grant

Support from the Hadassah-Hebrew University Pain Relief Unit

Harris et al. 2000

To better understand relationships between past experience with drugs and reasons for cannabis use; perceived effectiveness of cannabis as a therapeutic agent.

Quantitative: Questionnaires; recruitment via advertisements posted at the Cannabis Cultivator’s Club.

California, USA (after 1996)

Legal MC use.

100 Cannabis Cultivator’s Club members.

40 ± 8 years.

78% men.

33% AIDS (appetite)

21% musculoskeletal/arthritis

15% gastrointestinal (most often nausea)

15% psychiatric (primarily depression)

13% neurologic and non-musculoskeletal pain syndromes.

66% rated effectiveness as 80% compared with 52% for other medications.

56% reported no side effects.

Less severe side effects than other treatments. Anxiety effects frequently reported on the checklist but not listed as side effects.

Research grant

US Public Health Service grants, National Institute on Drug Abuse

Hazekamp & Heerdink, 2013

To analyze the incidence and prevalence of medical cannabis use and characteristics of users.

Quantitative: Retrospective database study; recruitment through the Dutch Foundation for Pharmaceutical Statistics and the only Dutch pharmacy specialized in medical cannabis dispensing.

Netherlands.

2003–2010, pharmaceutical-grade cannabis distributed for medicinal purposes since 2003.

5540 patients with ≥ 1 medical cannabis prescription.

56 (14–93) years.

43% men.

Reason for medical cannabis use not reported but 43% had analgesics prescribed in the 6-month period preceding start of MC use. Only 2.7% received oncologicals, thus cancer is unlikely to be present in all pain patients in the study.

not reported

N/A

Hazekamp et al. 2013

To compare different administration forms of cannabinoids and identify their relative advantages and disadvantages as described by actual users.

International, web-based, cross-sectional survey; recruitment via the official website of the International Association for Cannabinoid Medicines.

31 countries including the USA (40 states represented), Germany, France, Canada, Netherlands & Spain.

2009–2010, legality differed by country.

953 adults self-reporting experience with ≥ 2 different cannabinoid-based medicines or administration forms, 87% current medical cannabis users.

40.7 (14–76) years.

64% men.

Top 5 conditions:

12% back pain

7% sleeping disorder

7% depression

6% pain resulting from injury or accident

4% multiple sclerosis. Pain medication was consumed by 53.6% of medical cannabis users

Herbal medical cannabis received higher appreciation than pharmaceutical cannabinoids.

Side effects: irritation of the lungs (inhalation), drowsiness, uncontrollable appetite, “getting high”.

Non-governmental organization funding

Dutch Association for Legal Cannabis and its Constituents as Medicine (NCSM foundation)

Hoffman et al. 2017

To begin the development of a cannabis use registry in Oregon.

Qualitative: Semi-structured interviews; recruitment via an outpatient healthcare clinic.

Oregon, USA.

July–August 2015: legal medical cannabis use, nonmedical used became legal on July first.

22 qualified medical cannabis users.

Median 38 (20–64) years.

45% men.

59% musculoskeletal pain

27% PTSD.

Some reported physiologic relief from pain, others said it helped take their mind off of it.

Respondents felt that the benefits outweighed the risks.

Research grant

National Institute of Drug Abuse supported this study

Ilgen et al. 2013

To describe adults seeking medical cannabis;

To compare them with those renewing their medical cannabis card on substance use; pain; functioning.

Quantitative: Questionnaires; recruitment at the waiting room of an medical cannabis clinic.

Michigan, USA.

Legal medical cannabis use.

348 adults seeking medical cannabis certification either for the first time (56%) or as a renewal (44%).

41.5 ± 12.6 years.

66% men.

87% used medical cannabis for pain relief, including 7% for musculoskeletal problems.

Not reported

N/A

Kilcher et al. 2017

To study medical uses of cannabinoids as part of the Swiss Federal Office of Public Health (FOPH) programme of exceptional licenses.

Quantitative: Data from the formal requests for medical use of cannabinoids; recruitment via formal requests of medical cannabis use.

Switzerland.

2013–2014, exceptional licenses for medical use of cannabinoids.

1193 qualified medical cannabis users.

57 ± 15 years.

43% men.

Most common symptoms:49% chronic pain40% Spasticity

Diagnosis:25% musculoskeletal conditions22% multiple sclerosis.

Licences were initially granted for 6 months, physicians requested extensions when the treatment had been satisfactory. The number of extensions increased from 26% in 2013 to 39% in 2014.

N/A

Lavie-Ajayi & Shvartzman 2018

To evaluate the subjective experience of pain relief by medical cannabis.

Qualitative: In-depth semistructured interviews; recruitment through a pain clinic.

Israel.

2016–2017, legal medical cannabis use.

19 patients seeking treatment with medical cannabis.

52 (28–79) years.

53% men

Chronic pain:37% arthritis32% spinal cord injuries32% CRPS

5% cancer.

Immediate sensation of chronic pain relief, improved sleep quality, improved life quality.

Side effects: increased appetite (74%), drowsiness (67.1%), ocular irritation (40.7%), lack of energy (37.5%), memory impairment (31.6%), palpitations (15.4%), and paranoia (15.2%) or confusion (12.4%).

Research grant

Ben Gurion University of the Negev, Faculty of Humanities and Social Sciences.

Lintzeris et al., 2018

To explore patterns of medical cannabis use.

Quantitative: Online survey; recruitment trough online media, consumer group webpages, and medical cannabis consumer forums.

Australia.

2016, illegal medical cannabis use.

1748 medical cannabis users.

37.9 years.

68% men.

51% anxiety, 50% back pain, 49% depression, 44% sleep problems, 26% neck pain, 23% PTSD. 69.4% of respondents used medical cannabis to manage pain.

Most participants reported that medical cannabis reduced significantly chronic pain.

Side effects: increased appetite (74%), drowsiness (67%), ocular irritation (41%), lack of energy (38%), memory impairment (32%), palpitations (16%), paranoia (15%) or confusion (12%).

(Mixed)

Research grant

Australian Research Council and the National Health and Medical Research council (NHMRC)

Local research grant

Lambert Initiative for Cannabinoid Therapeutics

Lucas & Walsh 2017

To describe medical cannabis access, use and substitution for patients enrolled in the Canadian Marihuana for Medical Purposes regulations.

Quantitative: Online cross-sectional survey; recruitment through a licensed producer of cannabis.

Canada.

July 2015, legal medical cannabis use (Marihuana for Medical Purposes Regulations *).

271 qualified medical cannabis users (Marihuana for Medical Purposes Regulations).

40 (20–77) years.

73% men.

53% pain-related conditions:

36% chronic pain, 12% arthritis, 5% headache.

Most highly endorsed symptoms:

73% chronic pain, 60%, stress, 57% insomnia, 46% depression, 32% headache.

95% reported that cannabis often or always helped alleviate their symptoms.

Research grant

Institute for Healthy Living and Chronic Disease

Lynch et al. 2006

To describe medical cannabis users.

Quantitative: Structured follow-up questionnaire; recruitment of patients followed at a tertiary care pain management center.

Nova Scotia, Canada.

2001-2005, legal medical cannabis use (Marihuana Medical Access Regulations Marihuana Medical Access Regulations *).

30 qualified medical cannabis users (Marihuana Medical Access Regulations).

45 (31–61) years.

60% men.

Chronic severe pain that had not responded to traditional approaches:

47% neuropathic pain

13% low back pain

10% arthritis.

93% reported moderate or greater pain relief.

95% reported subjective improvement in function.

No serious adverse events reported.

N/A

Nunberg et al. 2011 and Reinarman et al. 2011

To describe medical cannabis users: demographics; symptoms; physician evaluations; conventional treatments tried; use practices.

Quantitative: Physician records and patients’ questionnaire; recruitment through nine medical cannabis clinics.

California, USA.

June–August 2006, legal medical cannabis use.

1746 medical cannabis applicants.

33% ≥ 45 years.

75% men.

82.6% report using medical cannabis to relieve pain.

58.2% diagnosed with chronic pain disorders, including:

26% low back pain

18% arthritis

2% fibromyalgia.

Patients typically report at least one therapeutic benefit:

83% relief of pain

41% muscle spasms

41% headache

38% anxiety

28% nausea and vomiting

26% depression.

(Mixed funding)

Research grant

RAND Corporation; Non-governmental organization funding

Cannabis “industry”

MediCann; Private Foundation

Rosenbaum Foundation

Ogborne et al. 2000

To explore reasons for medical cannabis use; medical cannabis effects; methods and patterns of use; experiences with physicians; encounters with the law.

Qualitative: Interview; recruitment through advertisements in newspapers and on bulletin boards at an Addiction Research Foundation and at different town locations (bookstores, grocery stores, restaurants, laundromats, etc).

Toronto, Canada.

Before the 2001 Marihuana Medical Access Program.

50 self-identified medical cannabis users.

38 (26–57) years.

66% men.

22% HIV/AIDS-related symptoms

14% chronic/recurrent pain due to injury of unknown origin

12% depression

2% arthritis.

medical cannabis described as superior to other treatments.

Reported lethargy, apathy, cough or throat irritation from smoking, thirst, loss of concentration, short-term memory loss, paranoia, and depression.

N/A

Pedersen & Sandberg 2013

To investigate the medical motives of Norwegian cannabis users.

Qualitative: Semi-structured interviews; recruitment through internet advertisements, authors‘ own social networks, among students at the University of Oslo, and from organizations such as the National Organization for the Reform of Marijuana Laws.

Norway.

2006–2010, illegal.

100 long-term cannabis users (25 stated explicitly they used cannabis medically).

20–62 years.

88% men.

Cannabis was used therapeutically for conditions such as multiple sclerosis, attention deficit hyperactivity disorder and rheumatism, as well as for quality of life conditions such as quality of sleep, relaxation and wellbeing.

Cannabis typically described as useful for treating stress, insomnia and pain, as well as for relaxation.

Research grant

Research Council of Norway

Perron et al. 2015

To better elucidate, among MC users with and without concurrent use of prescription pain medication (PPM): patterns of alcohol and other drug use; functioning; perceived efficacy of pain treatments.

Quantitative: Questionnaires; recruitment via a survey conducted among persons seeking medical cannabis certification or recertification at an medical cannabis certification clinic.

Michigan, USA.

Legal medical cannabis use.

273 adults reporting past-month cannabis use for pain-related purposes (subsample of Ilgen et al.’s 2013 study).

40.3 ± 12.5 years.

69% men.

Subset of subjects who endorsed using cannabis in the past month specifically for pain reduction.

Prescription pain medication (PPM) users perceived cannabis as more efficacious than PPMs.

Research grant

National Institute on Drug Abuse grant

Piper et al. 2017

To provide an in-depth qualitative exploration of patient perspectives on the strengths and limitations of medical cannabis.

Online survey with open-ended questions; recruitment via medical cannabis dispensaries.

Maine, Vermont, and Rhode Island, USA.

2015–2016 (chronic pain was not a condition to become part of the Vermont registry).

984 members of medical cannabis dispensaries.

49.1 ± 0.5 years.

47% men.

64% reported a diagnosis of chronic pain:91% back/neck pain30% neuropathic pain23% postsurgical pain22% abdominal pain20% chronic pain after trauma/injury.

75% relief of symptoms.

Reported benefits: pain relief, better sleep, safe/natural (limited addictive potential), quality of life, functionality.

Negative themes: respiratory effects, increased appetite, cognitive (decrease ability to concentrate, non-alert feeling…).

(Mixed)

Nonprofit organization funding

Center for Wellness Leadership

Local resource funding

Wellness Connection of Maine (Burstein, 2015); Research grant

National Institute of Drug Abuse

Reiman 2009

To examine drug and alcohol use, and the occurrence of substitution among medical cannabis users.

Quantitative: Survey data collected at a medical cannabis dispensing collective; recruitment through an medical cannabis dispensing collective.

California, USA.

Legal medical cannabis use.

350 medical cannabis users

39 (18–81) years.

68% men.

52% use cannabis for a pain related condition, including 45% who used it against pain resulting from an alcohol related accident.

75% use cannabis for a mental health issue.

65% use medical cannabis as a substitute for alcohol, illicit or licit drugs with less adverse side effects.

N/A

Reiman et al. 2017

To gather the impressions of patients who have used cannabis on how it compares with pain medications.

Quantitative: Cross-sectional survey; recruitment through e-mails addressed to medical cannabis patients of an medical cannabis patient database (67,422 patients).

California, USA.

2897 medical cannabis respondents seeking medical cannabis certification.

≥ 20 years.

55% men.

63% pain-related conditions including back pain and arthritis.

Respondents overwhelmingly reported that cannabis provided relief on par with their other medications, but without the unwanted side effects.

N/A

Sagy et al. 2019

To investigate the characteristics, safety and effectiveness of medical cannabis in fibromyalgia over a period of 6 months.

Quantitative: Questionnaire; recruitment via medical cannabis provider.

Israel.

2015–2017, legal medical cannabis use.

367 fibromyalgia patients, qualified medical cannabis users.

52.9 (± 15.1) years.

18% men.

100% fibromyalgia.

Overall pain intensity assessed by NRS reduced from a median of 9.0 at baseline to 5.0 after 6 months of medical cannabis treatment (P < 0.001).

Side effects: dizziness (7.9%), dry mouth (6.7%), nausea/vomiting (5.4%), hyperactivity (5.5%), increased appetite (3.8%).

N/A

Schnelle et al. 1999

Quantitative: questionnaire; recruitment via an medical cannabis association.

Germany, Austria and Switzerland.

1998-1999.

128 qualified medical cannabis users.

37.5 ± 9.6 y

68% men

12% depression

11% multiple sclerosis

9% HIV infection

5% back pain.

Symptoms improvement from much (72.2%), to none (4.8%).

1.6% experienced worsening of symptoms.

70.8% experiences no adverse effects.

N/A

Sexton et al. 2016

To collect epidemiologic data to inform medical practice, research, and policy to provoke discussion about the discrepancies between medico-legal recommendations and patient-reported outcomes.

Quantitative: Cross-sectional online survey); recruitment through links posted on University (Bastyr University California (US)) websites, social media and cannabis dispensaries.

Respondents came from 18 countries, with the USA (78%), the UK (6%), and Canada (3%) being the most represented.

2013–2016.

Legality varies across countries.

Convenience sample of 1429 self-identified medical cannabis users.

36.3 ± 14 (15-80) years.

55% men.

61% pain

58% anxiety

50% depression

35.5% headache/migraine

27% nausea

18% muscle spasticity

17% arthritis

15% irritable bowel

11.5% intractable pain.

On average, participants reported an 86% reduction in symptoms.

Research grant

NIH NCCAM K01ATTA (Ste-Marie et al., 2016)

Shah et al. 2017

To examine clinical and treatment characteristics for patients who are admitted to a 3-week outpatient inter-disciplinary chronic pain rehabilitation program.

Quantitative: Self-report questionnaire and chart review; recruitment of patients admitted to a 3-week outpatient inter-disciplinary chronic pain rehabilitation program.

The USA.

March–December 2015.

Not reported

24 patients with THC positive urine test participating to a pain rehabilitation program.

45.4 ± 15.3 years.

42% men.

Chronic pain.

Not reported

N/A

Shiplo et al. 2016

To examine modes of medical cannabis delivery following regulatory changes in 2014.

Quantitative: Online cross-sectional survey; recruitment via nine Health Canada licenced medical cannabis producers.

Canada.

April–June 2015.

Legal medical cannabis use.

Convenience sample of 364 qualified medical cannabis users.

40.8 ± 12.6 years.

58% men.

45% for pain relief (chronic pain and fibromyalgia)

15% mental health

10% central nervous system.

not reported

Research grant

Canadian Institute of Health Research (CIHR) Training Grant Program in Population Intervention for Chronic Disease Prevention

Ste-Marie et al. 2012

To document the self-identified prevalence of cannabinoid use in fibromyalgia patients seen in a fibromyalgia clinic.

Qualitative: Retrospective chart review; recruitment via a tertiary care pain center.

Montreal, Canada.

2005–2010.

Legal medical cannabis use.

59 medical cannabis users with a diagnosis of fibromyalgia. 24% used prescription cannabinoids.

45 ± 10 y

33% men.

Fibromyalgia (61%) or regional pain syndrome and spinal pain, rheumatic disease, neurologic condition.

Not reported

Research grant

Louise and Alan Edwards Foundation

Ste-Marie et al. 2016

To examine the prevalence of cannabis use among rheumatology patients.

To compare the clinical characteristics of medical cannabis users and nonusers.

Quantitative: Cross-sectional survey (questionnaires); recruitment via an university-affiliated community rheumatology clinic.

Ontario, Canada.

April–May 2014.

Legal medical cannabis use.

28 current medical cannabis users.

52.7 ±13.6 years.

43% men.

15 previous medical cannabis users, 62.8 ± 14.4 y, 26% men.

Specific rheumatic disease :

54% osteoarthritis or spinal pain

32% inflammatory arthritis

18% fibromyalgia.

Medical cannabis reported to relieve pain, anxiety, nausea, improve sleep and appetite.

Research grant

Louise and Alan Edwards Foundation

Swift et al. 2005

To learn more about: patterns of use; experiences and concerns; interest in participating in a medical cannabis trial.

Quantitative: Mailed questionnaires; recruitment through opportunistic media stories in newspapers, on radio and television.

Australia.

2003-2004.

Illegal.

128 medical cannabis users

Median 45 (24–88) years.

63% men.

Condition:

60% depression

53% chronic pain

38% arthritis.

86% reported great relief from cannabis.

Typically perceived as superior to other medications in terms of undesirable effects, and the extent of relief provided.

15% had stopped, 16% disliked the side effects or route of use (each 3/19).

N/A

Troutt & DiDonato, 2015

To examine medical cannabis users: characteristics; perceptions; behaviors.

To learn about experiences with cannabis before legalization.

Quantitative: Anonymous online survey; recruitment: via four medical cannabis dispensaries.

Arizona, USA.

After the 2012 Arizona Department of Health Services Medical Marijuana Rules.

367 patients recruited from medical cannabis dispensaries.

45.78 ± 13.76 (18–83) years.

64% men.

87% chronic pain

24.5% arthritis

11% osteoarthritis

7% fibromyalgia.

70% experienced a lot of or almost complete relief.

N/A

Walsh et al. 2013 and Belle-Isle et al. 2014

To examine: cannabis use history; medical conditions and symptoms; patterns of use; modes of access; perceived effectiveness.

Quantitative: Survey (online or at a cannabis dispensary); recruitment through local medical cannabis dispensaries and national organizations that assist medical cannabis users.

British Columbia, Canada.

2011–2012.

Legal medical cannabis use.

628 self-identified current medical cannabis users.

39.1 ± 13.1 years.

71% men.

Pain, including chronic, spinal and non-spinal pain, arthritis (82%), anxiety, and sleep problems.

Cannabis perceived to provide effective symptoms relief:

72% reported medical cannabis always helpful, 24% often helpful.

Research grant

UBC Institute for Healthy Living and Chronic Disease Prevention

Ware et al. 2003

To determine current prevalence of medical cannabis in chronic non-cancer pain; estimate the dose size and frequency of cannabis use; describe main symptoms for which relief was sought.

Quantitative: Cross-sectional survey; recruitment of all patients entering the ambulatory pain management unit of the Queen Elizabeth II Health Sciences Center.

Nova Scotia, Canada.

June to July 2001.

Legal medical cannabis use.

09 chronic non-cancer pain patients.35% had ever used cannabis, 15% have used cannabis for pain relief, and 10% were current MC users for pain relief.

Of MC users:

50% trauma/surgery

6% arthritis

6% multiple sclerosis.

Improved pain, sleep and mood.

78% of medical cannabis users reported at least moderate relief of pain.

25% reported no side effects, 37% very mild, 28% moderate, 9% strong side effects, no severe side effects.

(Mixed)

University funding

*Faculty of Medicine

*Department of Anesthesia; Non-governmental organization funding

Research-based pharmaceutical companies

Webb & Webb 2014

To discover the benefits and adverse effects perceived by medical cannabis users, especially with regards to chronic pain.

Quantitative: Survey (questionnaires); recruitment via questionnaires hand-delivered to medical cannabis certified patients re-applying for certification.

Hawaii, USA.

2010–2011.

Legal MC use.

94 patients re-applying for medical cannabis certification.

49.3 years.

97% used cannabis primarily for chronic pain.

64% relative decrease in average pain.

71% reported no adverse effects, 6% reported a cough or throat irritation.

N/A

Zaller et al. 2015

To characterize socio-demographics and reasons for medical cannabis use among dispensary patients.

Quantitative: Cross-sectional survey (questionnaires); recruitment through Compassion Centers of the Department of Health.

Rhode Island, USA.

After the 2013 authorization for medical cannabis dispensaries.

200 qualified medical cannabis users.

Median 41 (18–76) years.

73% men.

The most common reason for medical cannabis use was chronic pain management.

Most participants report that medical cannabis improves their pain symptomology.

91.5% report less unwanted side effects than with prescription medications.

N/A