Abstract
Introduction:
Endometriosis is a difficult to manage condition associated with a significant disease burden. High levels of illicit cannabis use for therapeutic purposes have been previously reported by endometriosis patients in Australia and New Zealand (NZ). Although access to legal medicinal cannabis (MC) is available through medical prescription via multiple federal schemes, significant barriers to patient access remain.
Methods:
An anonymous cross-sectional online survey was developed and distributed through social media via endometriosis advocacy groups worldwide. Respondents were asked about legal versus illicit cannabis usage, their understanding of access pathways and legal status, and their interactions with health care professionals.
Results:
Of 237 respondents who reported cannabis use with a medical diagnosis of endometriosis, 186 (72.0%) of Australian and 51 (88.2%) NZ respondents reported self-administering cannabis illicitly. Only 23.1% of Australian and 5.9% of NZ respondents accessed cannabis through a doctor's prescription, with 4.8% of Australian and no NZ respondents reporting to legally self-administer cannabis. Substantial substitution effects (>50% reduction) were observed in users of nonopioid analgesia (63.1%), opioid analgesia (66.1%), hormonal therapies (27.5%), antineuropathics (61.7%), antidepressants (28.2%) and antianxiety medications (47.9%). Of Australian respondents, 18.8% and of NZ respondents, 23.5% reported not disclosing their cannabis use to their medical doctor, citing concern over legal repercussions, societal judgment, or their doctors' reaction and presumed unwillingness to prescribe legal MC.
Conclusions:
Respondents self-reported positive outcomes when using cannabis for management of endometriosis, demonstrating a therapeutic potential for MC. Despite this, many are using cannabis without medical supervision. While evidence for a substantial substitution effect by cannabis was demonstrated in these data, of particular concern are the clinical consequences of using cannabis without medical supervision, particularly with regard to drug interactions and the tapering or cessation of certain medications without that supervision. Improving doctor and patient communication about MC use may improve levels of medical oversight, the preference for legal MC adoption over acquisition via illicit supply and reducing cannabis-associated stigma.
Keywords: cannabis, medicinal cannabis, survey, endometriosis, legal barriers
Introduction
Endometriosis is an estrogen-dependent chronic inflammatory condition that affects ∼10–15% of women of reproductive age,1 and it is estimated that by the age of 44, one in nine women will have been diagnosed with endometriosis in Australia2 with a diagnostic delay of 6–8 years.3,4 Endometriosis is characterized by the presence of endometrial-like tissue outside of the uterus, with severe pain and fatigue being two of the most difficult symptoms for women to manage.5
Previous research has shown that women with endometriosis in Australia6 and New Zealand (NZ)7 report that cannabis usage, mostly illicit, has resulted in a reduction in their pharmaceutical medications, most commonly, opioid analgesics. Medicinal cannabis (MC) can be prescribed under strict regulations in Australia and NZ. In Australia, there are three Federal schemes by which MC can be prescribed: via the Authorised Prescriber (AP) Scheme, the Special Access Scheme (SAS) Category B, or as part of a clinical trial.8
MC prescription was historically more difficult in NZ, requiring the approval by the Ministry of Health through a medical specialist application.9 However, since April 2020, any medical practitioner is allowed to prescribe government-approved MC for any indication where there is clinical need.10
Given the historical differences in legal access between countries, there may be differing rates of MC uptake between Australia and NZ, and especially a potential reliance on illicit sources in NZ, compared to Australia, due to this. It is also unclear to what extent people with endometriosis in Australia or NZ discuss their cannabis usage (whether legal or not) with their doctor, if doctors are actively prescribing MC for endometriosis, what concurrent medications are being used, and any potential risks for reducing or stopping these.
Materials and Methods
Sample and recruitment
This survey was approved in December 2020 by the Western Sydney University Human Research Ethics Committee (Approval No. H14115). This anonymous survey was hosted on the Qualtrics platform (Qualtrics Ltd.). This survey was open worldwide and required ∼15–30 min to complete. This study only reports on data from Australian and NZ participants. Features were enabled within Qualtrics that ensured anonymity due to potential disclosure of illegal activities, including no cookies being used, no IP addresses being recorded, or no identifying information being collected as part of the survey itself. The survey was open for 6 weeks between mid-January 2021, with the Australian and NZ respondent data closed on March 1st, 2021.
Subjects were eligible to participate if they had a medical diagnosis of endometriosis, were aged between 18 and 55 years, and had used cannabis or phytocannabinoid-based products (e.g., CBD oil, whole cannabis oils, legal dried flowers [“buds”] with known levels of THC and/or CBD, or nonlegal forms of cannabis) in the past 3 months specifically for the purpose of managing their endometriosis pain and/or related symptoms. Recruitment was conducted via the social media platforms of Endometriosis Australia and Endometriosis NZ, the two main endometriosis advocacy, education, and support groups in Australia and NZ with the most followers on social media (>50,000 combined in early 2021).
Outcomes
Demographic information, including age, location, endometriosis symptoms, and current management approaches were collected. Questions about cannabis usage were dependent on the form of cannabis used, but included changes in medications, and discussion of cannabis usage with health care professionals.
Data analysis
Data analyses were conducted using IBM SPSS (Version 27). Descriptive statistics were presented as means and standard deviations for parametric data, medians, and interquartile ranges for nonparametric data and numbers and percentages for categorical data. Values were considered statistically significant if p<0.05. Inferential statistics comparing groups were performed using the chi square test of independence. Missing data were not replaced.
Results
Eligible responses were received from 237 respondents currently residing in Australia or NZ. Of eligible respondents, 78.5% were Australian and 21.5% were from NZ. Of the respondents, 78.5% were from urban locations across both Australia and NZ. Table 1 outlines the demographics, endometriosis symptoms, and current management strategies of respondents in both countries.
Table 1.
Demographics, Symptoms, and Current Management Strategies
| Australian (N=186) | New Zealanders (N=51) | Combined (N=237) | |
|---|---|---|---|
| Age (mean±SD) | 30.05 (6.7) | 31.92 (6.9) | 30.45 (6.8) |
| Years since diagnosis, mean (SD) | 6.14 (6.3) | 9.78 (7.2) | 6.92 (6.6) |
| Current symptoms, n (%) | |||
| Fatigue | 174 (93.5) | 50 (98.0) | 224 (94.5) |
| Chronic pelvic pain | 173 (93.0) | 46 (90.2) | 219 (92.4) |
| Bowel symptoms | 166 (89.2) | 46 (90.2) | 212 (89.5) |
| Back pain | 156 (83.9) | 44 (86.3) | 200 (84.4) |
| Anxiety | 156 (83.9) | 42 (82.4) | 198 (83.5) |
| Dysmenorrhea | 153 (82.3) | 40 (87.4) | 193 (81.4) |
| Dyspareunia | 135 (72.6) | 38 (74.5) | 173 (73.0) |
| Nausea | 130 (69.9) | 40 (78.4) | 170 (71.7) |
| Difficulties with sleep | 131 (70.4) | 34 (66.7) | 165 (69.6) |
| Headache or migraine | 125 (67.2) | 36 (70.6) | 161 (67.9) |
| Gastrointestinal symptoms | 129 (69.4) | 31 (60.8) | 160 (67.5) |
| Depression | 122 (65.6) | 34 (66.7) | 156 (65.8) |
| Bladder symptoms | 116 (62.4) | 25 (49.0) | 141 (59.5) |
| Heavy menstrual bleeding | 92 (49.5) | 22 (43.1) | 114 (48.1) |
| Other | 24 (12.9) | 4 (7.8) | 28 (11.8) |
| Current medications and treatments, n (%) | |||
| Nonopioid pain medication | 145 (78.0) | 44 (86.3) | 189 (79.7) |
| Opioid-based pain medication | 97 (52.2) | 31 (60.8) | 128 (54.0) |
| Hormonal treatment | 93 (50.0) | 31 (60.8) | 124 (52.3) |
| Antinausea medication | 57 (30.6) | 26 (51.0) | 83 (35.0) |
| Physiotherapy/pelvic exercises | 68 (36.6) | 13 (25.5) | 81 (34.2) |
| Antidepressant medications | 59 (31.7) | 20 (39.2) | 79 (33.3) |
| Antianxiety medications | 51 (27.4) | 10 (19.6) | 61 (25.7) |
| Acupuncture or traditional Chinese medicine treatment | 36 (19.4) | 6 (11.8) | 42 (17.7) |
| Other | 34 (18.3) | 7 (13.7) | 41 (17.3) |
| Herbal medicine | 30 (16.1) | 8 (15.7) | 38 (16.0) |
| Neuroleptic medication | 24 (12.9) | 11 (21.6) | 35 (14.8) |
| Sleeping medications | 21 (11.3) | 8 (15.7) | 29 (12.2) |
SD, standard deviation.
Medication changes (i.e., substitution effect) with cannabis
Combined respondent data reported (see Appendix Table AT1) cessation or significant reductions (defined as a decrease in medication by >50%) across a variety of medications, including opioids (31.1% complete cessation, 35% significant reduction), nonopioid analgesia (17.2% complete cessation, 45.9% significant reduction), hormonal treatments (20.6% complete cessation), and antineuropathics (51% complete cessation). Of the 96 respondents previously on antidepressant and antianxiety medication, complete cessation data were reported as 21.9% and 27.1%, respectively.
Understanding of legality and access pathways
Respondents were asked to report the legal status of accessing cannabis in their respective locations. For the Australian cohort, 3.8% reported legal access for both recreational and medical purposes with 47.8% reporting legal access for medicinal use only, 8.1% reported only decriminalized access, and 40.3% reported only illicit access. For the NZ cohort, no respondents reported legal access for recreational and medical purposes, 37.3% reported legal access for medicinal use only, no respondents reported only decriminalized access, and 62.7% reported only illicit access.
When asked about their access to cannabis, 72.0% of Australian respondents and 88.2% of NZ respondents reported that they self-administer illicit cannabis for therapeutic purposes, with only 23.1% of Australian respondents and 5.9% of NZ respondents reporting MC access via doctor's prescription, with 4.8% of Australian respondents and no (0%) NZ respondents reporting that they legally self-administered. There was a significant difference in access pathways reported between Australian and New Zealander respondents [χ2 (2, N=237)=7.6 p=0.02].
Motivation for cannabis usage
Table 2 outlines the motivation for cannabis usage of participants in both countries.
Table 2.
Motivation for Cannabis Usage
| Australian (N=186) |
New Zealander (N=51) |
Combined (N=237) |
|
|---|---|---|---|
| n (%) | n (%) | n (%) | |
| Inadequate pain control from pharmaceutical medications | 131 (70.4) | 40 (78.4) | 171 (72.2) |
| Side effects of pharmaceutical medications were intolerable | 103 (55.4) | 35 (68.6) | 138 (58.2) |
| Was utilizing cannabis recreationally and noticed pain and/or symptom reduction | 90 (48.4) | 28 (54.9) | 118 (49.8) |
| Recommended by an endometriosis support group | 77 (41.4) | 16 (31.4) | 93 (39.2) |
| Recommended by a friend or work colleague with endometriosis | 51 (27.4) | 20 (39.2) | 71 (30.0) |
| Difficulty in finding access to medical expertise on endometriosis in your region | 47 (25.3) | 11 (21.6) | 58 (24.5) |
| Lack of finances/insurance to afford surgery for endometriosis | 26 (14.0) | 9 (17.6) | 35 (14.8) |
| Recommended by a medical professional | 24 (12.9) | 7 (13.7) | 31 (13.1) |
| Lack of finances/insurance to afford pharmaceutical medications for endometriosis | 22 (11.8) | 7 (13.7) | 29 (12.2) |
| Other (Please explain) | 15 (8.1) | 3 (5.9) | 18 (7.6) |
| Delayed or cancelled surgery due to COVID-19 | 10 (5.4) | 4 (7.8) | 14 (5.9) |
Communication with health professionals
Table 3 outlines if respondents discussed their cannabis usage with health professionals and the reasons behind why they did or did not.
Table 3.
Communication with Health Professionals
| Australian (N=186), n (%) | New Zealanders (N=51), n (%) | Combined, n (%) | |
|---|---|---|---|
| Did you inform your doctor about your cannabis usage? | |||
| Yes—cannabis usage was their suggestion | 18 (9.7) | 4 (7.8) | 22 (9.3) |
| Yes—cannabis usage was my idea, but I informed them | 84 (45.2) | 25 (49.0) | 109 (46.0) |
| Not yet—but I intend to tell them | 49 (26.3) | 10 (19.6) | 59 (24.9) |
| No—I do not intend to tell them | 35 (18.8) | 12 (23.5) | 47 (19.8) |
| Reasons for not informing doctor | |||
| Concerned about legal repercussions | 7 (19.4) | 8 (66.7) | 15 (31.3) |
| Concerned about societal judgment | 12 (33.3) | 2 (16.7) | 14 (29.2) |
| Concerned about doctor's reaction | 12 (33.3) | 2 (16.7) | 14 (29.2) |
| Presumed doctor unwillingness to prescribe | 5 (13.9) | 0 (0.0) | 5 (10.4) |
Discussion
Both cohorts in this survey reported similar endometriosis-related symptoms with fatigue, chronic pelvic pain, and bowel symptoms being the most common. Usage of opioid and nonopioid medication for symptom management was common, irrespective of location. Almost three-quarters of respondents reported using cannabis due to suboptimal pain management of their endometriosis, and over half due to the side effects of their previously prescribed pharmaceutical medications. Almost all respondents reported that they would continue to use cannabis for their endometriosis as it provides better pain relief than current treatments.
Substitution effects were commonly observed, with two-thirds of respondents either ceasing or significantly reducing their use of opioids. However, respondents often lacked an understanding of the legal access pathways available within their respective countries for obtaining MC, and commonly did not communicate their cannabis usage to their doctors, often for perceived concerns about legal or societal repercussions.
Despite MC being a legal medicine when prescribed by a medical doctor in both Australia and NZ, most respondents still reported illicit, rather than legal MC usage. While MC preparations and patient access are approved by regulatory bodies, such as the Therapeutic Goods Administration (TGA) in Australia, illicit cannabis lacks the quality assurance and standardization of active cannabinoids that are required for regulatory compliance,11 posing a public health concern. Illicit Cannabis plant varieties often contain unknown quantities of cannabinoids, causing challenges for ensuring consistent clinical reproducibility, and are typically bred to have higher THC content, possibly contributing to greater cognitive impairment.12 Of particular concern is that illicit cannabis may be contaminated with molds, heavy metals, bacteria, or pesticide residues, which may pose additional safety risks.11 Current data reported by the United Nations suggest that Australia and NZ are among the highest illicit cannabis users in the world per capita, with a meaningful portion seeking therapeutic benefit.13 This prevalence may be partly due to a lack of understanding of MC legal access pathways, which was apparent in the present study, with over half of the respondents being unaware of any legal means of accessing MC.
Australian Senate inquiry findings14 have demonstrated that patients are using illicit cannabis for a variety of reasons, including the high cost of MC (due to it being grown in compliance with both Good Agricultural & Collection Practices [GACP] and Good Manufacturing Practice [GMP], which drives up costs due to regulatory compliance), concerns over privacy (including possible breaches of medical records), and an unwillingness to discuss cannabis use with doctors, a finding supported by the present study, where one in five respondents would not tell their doctors about their cannabis usage.
This communication barrier between doctors and their patients regarding cannabis use is evident among respondents, and is consistent with previous findings about cannabis use.15 Among Australian and NZ respondents, reasons for nondisclosure included fear of legal consequences, fear of stigma, and doctors' presumed nonsupportive reactions. Conversely, doctors have previously reported that lack of knowledge, lack of clinical evidence, and unknown side effects hinder the discussion and prescription of MC for patients.16–20 This hesitation by doctors to prescribe MC is apparent in our study, as only a minority of respondents reported using MC through a doctor prescription or recommendation. While it is encouraging to note that 55.3% of combined respondents had told their doctor about their cannabis use, 44.7% had not. Doctors' lack of awareness about a patients' cannabis use carries several clinical safety concerns. First, cannabis may interact pharmacodynamically with several medications, such as opioids21 and benzodiazepines,22 and increase the risk of adverse effects. Second, medications such as antidepressants can increase systemic levels of THC, augmenting the effects of cannabis.22
In addition, CBD-based products, which patients may be accessing illicitly from overseas supply chains and online sites, carry risk of pharmacokinetic interactions (particularly at higher doses) with numerous drug classes, including blood thinners.23 Given that most of our respondents reported taking pharmaceutical medications for various clinical indications, which is typical in chronic pain conditions,24 their nondisclosure of cannabis use to their doctors is concerning and could lead to negative clinical outcomes. Furthermore, commonly used medications by our respondents such as opioids, antidepressants, and antineuropathics require continuous dosage monitoring, and their cessation without appropriate tapering may cause withdrawal symptoms.25–27
Other medications, such as hormonal therapies, require a certain dose and frequency of administration to have sustained therapeutic benefit, therefore, reducing them when not under medical supervision may negatively impact the patient's symptoms.28,29 Recommendations on how clinicians should discuss cannabis30 show that clinicians should apply positive attitudes, listen effectively, express empathy, and inform themselves about therapies with which they are unfamiliar to establish better rapport with patients and foster improved communication.31,32
Our respondents reported a large and clinically relevant substitution effect, in line with previous data.6,33,34 The use of cannabis among endometriosis patients in Australia and NZ was associated with complete cessation or significant reduction in the use of several medication classes, including opioid and nonopioid analgesics, antineuropathics, anxiolytics, and sleeping medications. This is consistent with previous research suggesting reasons for substitution are better symptom management, reduced side effects, and fewer withdrawal symptoms.34,35 It is well established that long-term use of opioids and benzodiazepines is linked to dependency, sedation, cognitive impairment, hyperalgesia, overdose, and high incidental mortality rate,36–39 so substitution with cannabis may reduce these risks.40,41
Notwithstanding, long-term data regarding safety and efficacy of MC are still limited,42,43 but adverse effects from recreational use such as habituation, impaired cognition, schizophrenia, and respiratory conditions have been documented.44 A more immediate side effect of cannabis is functional impairment caused by being under the immediate influence of THC, the main intoxicating cannabinoid. This can affect the cognitive and motor skills necessary for driving or certain work-related activities, including attention, judgment, memory, vision, and coordination.45
Any amount of THC detected while driving is illegal in both Australia and NZ, and can be detected by roadside saliva tests.46 Although mere detection of THC in the body does not necessarily correspond to any degree of functional impairment, these laws may discourage MC usage in individuals who need to drive, or when drug testing is part of their employment policy, for fear of legal repercussions.47 The side effects of cannabis, in conjunction with the current roadside drug driving tests and Workplace Health & Safety (WHS) laws may, therefore, pose a barrier to the complete substitution of medications with MC, at least until the exemptions mandated for other prescription medications are likewise implemented.
The findings of the present study have wide-ranging clinical implications. With emerging evidence of self-reported effectiveness of cannabis usage in endometriosis,6,33,48 and the role of the endocannabinoid system in the pathophysiology of endometriosis,49,50 further clinical trials assessing the safety and feasibility of MC usage in managing endometriosis symptoms are urgently needed. Our results highlighted that respondents' have a limited understanding of MC access pathways. Similarly, doctors in Australia16 and NZ17 also report a lack of understanding of the emerging laws and clinical evidence regarding MC. Poor doctor knowledge is linked to poor quality care, therefore providing educational programs covering clinical indications, MC pharmacological effects, and combating the impact of social stigma and legalities is crucial.16
Patients are also in need of accurate information resources, through such sources as their physicians, websites, and pamphlets. The patient's nondisclosure to doctors revealed in our study also needs to be addressed, with barriers to communication identified and rectified. Finally, reassessing legal and regulatory measures regarding MC in Australia and NZ, given their overly restrictive nature, would be highly instrumental for increasing access to quality-assured medically prescribed MC.
There are several limitations to this study, which are important to discuss. Survey responses are prone to recall bias,51 which may influence responses, and nonresponse bias, which could skew the sample population52 toward people who are pro-cannabis, have more severe symptoms or who felt more compelled to complete the survey. Sampling bias is also recognized, as the present survey was distributed via social media53 to endometriosis advocacy and support groups, which could skew results to include people more greatly impacted by their endometriosis than is the case in the general population.54 Despite this, the present findings are consistent with previous studies of a similar magnitude and design.6,55
While all participants were advised that the survey was anonymous, it is possible that some respondents may still have concerns disclosing illegal activity and therefore the rate of illicit use may be higher than reported. Finally, as the social media followers for endometriosis support groups include both the target population (those with endometriosis) and also those not eligible to participate (family, friends, partners, etc.), it is impossible to determine accurate response rates. The total number of responses is lower than many recent surveys in this population4,56–58 and therefore may not be generalizable to the wider endometriosis population. A future combination of web-based and clinician-led surveys may be required to gain a more representative cross section.
Conclusion
The findings of this cross-sectional study suggest that cannabis is frequently used as an alternative strategy for pain management in women with endometriosis in Australia and NZ, mainly in illicit forms. This use was associated with a substantial substitution effect amounting to cessation of, or substantial reduction in, pharmaceutical medications, but raises clinical concerns of using cannabis without medical supervision, particularly with regard to drug interactions and the tapering of certain drugs such as benzodiazepines, antidepressants, and opioids. More open communication between medical professionals and patients is paramount to improve both clinical outcomes and improve patient safety.
In both Australia and NZ, MC can be prescribed for endometriosis, but access can be difficult with the current strict regulatory frameworks and high costs. Further interventional studies to determine the long-term safety profile of MC should empower physicians with higher quality evidence to prescribe MC and overcome legal barriers.
Acknowledgments
Thanks go to Endometriosis Australia and Endometriosis New Zealand for their support in this project.
Abbreviations Used
- CBD
cannabidiol
- MC
medicinal cannabis
- NZ
New Zealand
- THC
tetrahydrocannabinol
Appendix Table A1. Change in Pharmacotherapy amongst Respondents
| Change in pain management pharmacotherapy | Australia (N=186), n (%) | NZ (N=51), n (%) | Combined (N=237), n (%) |
|---|---|---|---|
| Nonopioids | |||
| Completely stopped | 36 (19.7) | 4 (8.0) | 40 (17.2) |
| Significant reduction (>50%) | 82 (44.8) | 25 (50.0) | 107 (45.9) |
| Moderate reduction (25–50%) | 38 (20.8) | 11 (22.0) | 49 (21.0) |
| Minimal reduction (<25%) | 14 (7.7) | 6 (12.0) | 20 (8.6) |
| No change | 12 (6.6) | 3 (6.0) | 15 (6.4) |
| Increased medication usage | 1 (0.5) | 1 (2.0) | 2 (0.9) |
| Opioids | |||
| Completely stopped | 47 (33.3) | 10 (23.8) | 57 (31.1) |
| Significant reduction (>50%) | 43 (30.5) | 21 (50.0) | 64 (35.0) |
| Moderate reduction (25–50%) | 29 (20.6) | 9 (21.4) | 38 (20.8) |
| Minimal reduction (<25%) | 16 (11.3) | 2 (4.8) | 18 (9.8) |
| No change | 6 (4.3) | 0 (0) | 6 (3.3) |
| Increased medication usage | 0 (0) | 0 (0) | 0 (0) |
| Hormonal | |||
| Completely stopped | 19 (19.2) | 8 (25.0) | 27 (20.6) |
| Significant reduction (>50%) | 6 (6.1) | 3 (9.4) | 9 (6.9) |
| Moderate reduction (25–50%) | 5 (5.1) | 4 (12.5) | 9 (6.9) |
| Minimal reduction (<25%) | 5 (5.1) | 1 (3.1) | 6 (4.6) |
| No change | 62 (62.6) | 15 (46.9) | 77 (58.8) |
| Increased medication usage | 2 (2.0) | 1 (3.1) | 3 (2.3) |
| Neuroleptic | |||
| Completely stopped | 20 (52.6) | 11 (50.0) | 31 (51.7) |
| Significant reduction (>50%) | 2 (5.3) | 4 (18.2) | 6 (10.0) |
| Moderate reduction (25–50%) | 5 (13.2) | 1 (4.5) | 6 (10.0) |
| Minimal reduction (<25%) | 1 (2.6) | 4 (8.2) | 5 (8.3) |
| No change | 10 (26.3) | 2 (9.1) | 12 (20.0) |
| Increased medication usage | 0 (0.0) | 0 (0.0) | 0 (0) |
| Antidepressant | |||
| Completely stopped | 15 (20.8) | 6 (25.0) | 21 (21.9) |
| Significant reduction (>50%) | 5 (6.9) | 1 (4.2) | 6 (6.3) |
| Moderate reduction (25–50%) | 3 (4.2) | 4 (16.7) | 7 (7.3) |
| Minimal reduction (<25%) | 7 (9.7) | 2 (8.3) | 9 (9.4) |
| No change | 38 (52.8) | 11 (45.8) | 49 (51.0) |
| Increased medication usage | 4 (5.6) | 0 (0.0) | 4 (4.2) |
| Antianxiety | |||
| Completely stopped | 18 (24.3) | 8 (36.4) | 26 (27.1) |
| Significant reduction (>50%) | 15 (20.3) | 5 (22.7) | 20 (20.8) |
| Moderate reduction (25–50%) | 10 (13.5) | 3 (13.6) | 13 (13.5) |
| Minimal reduction (<25%) | 9 (12.2) | 3 (13.6) | 12 (12.5) |
| No change | 19 (25.7) | 3 (13.6) | 22 (22.9) |
| Increased medication usage | 3 (4.1) | 0 (0.0) | 3 (3.1) |
| Sleeping medication | |||
| Completely stopped | 20 (33.3) | 9 (42.9) | 29 (35.8) |
| Significant reduction (>50%) | 18 (30.0) | 7 (33.3) | 25 (30.9) |
| Moderate reduction (25–50%) | 7 (11.7) | 2 (9.5) | 9 (11.1) |
| Minimal reduction (<25%) | 7 (11.7) | 2 (9.5) | 9 (11.1) |
| No change | 5 (8.3) | 1 (4.8) | 6 (7.4) |
| Increased medication usage | 3 (5.0) | 0 (0.0) | 3 (3.7) |
| Antinausea | |||
| Completely stopped | 13 (16.5) | 7 (25.0) | 20 (18.7) |
| Significant reduction (>50%) | 22 (27.8) | 11 (39.3) | 33 (30.8) |
| Moderate reduction (25–50%) | 18 (22.8) | 5 (17.9) | 23 (21.5) |
| Minimal reduction (<25%) | 8 (10.1) | 2 (7.1) | 10 (7.5) |
| No change | 16 (20.3) | 2 (7.1) | 18 (15.0) |
| Increased medication usage | 2 (2.5) | 1 (3.6) | 3 (1.9) |
Author Disclosure Statement
As a Medical Research Institute, NICM Health Research Institute receives research grants and donations from foundations, universities, government agencies, individuals, and industry. Sponsors and donors also provide untied funding for work to advance the vision and mission of the Institute. The authors declare no competing financial interests. J. Sinclair is the recipient of a Western Sydney University Postgraduate Research Scholarship and is employed by Australian Natural Therapeutics Group. J. Sinclair also sits on the board of the Australian Medicinal Cannabis Association (pro bono) and the scientific advisory board of United in Compassion (pro bono).
J. Sarris is an Executive Director of a not-for-profit research institute studying psychedelic medicines (and indirectly receives commercial salary support for this work). He also has received either presentation honoraria, travel support, clinical trial grants, book royalties, or independent consultancy payments from Australian Natural Therapeutics Group (being a scientific advisor to Australian Natural Therapeutics Group: a cannabis grower and manufacturer), Integria Healthcare & MediHerb, Pfizer, Scius Health, Key Pharmaceuticals, Taki Mai, Fiji Kava (as an independent scientific advisor), FIT-BioCeuticals, Blackmores, Soho-Flordis, Healthworld, HealthEd, HealthMasters, Kantar Consulting, Angelini Pharmaceuticals, Grunbiotics, Polistudium, Research Reviews, Elsevier, Chaminade University, International Society for Affective Disorders, Complementary Medicines Australia, SPRIM, Terry White Chemists, ANS, Society for Medicinal Plant and Natural Product Research, Sanofi-Aventis, Omega-3 Centre, the National Health and Medical Research Council, and the CR Roper Fellowship.
Funding Information
J. Sarris is supported by an NHMRC Clinical Research Fellowship (APP1125000). No specific funding was received for this research, which forms part of a PhD research project for J. Sinclair.
Cite this article as: Sinclair J, Toufaili Y, Gock S, Pegorer AG, Wattle J, Franke M, Alzwayid MAKM, Abbott J, Pate DW, Sarris J, Armour M (2022) Cannabis use for endometriosis: clinical and legal challenges in Australia and New Zealand, Cannabis and Cannabinoid Research 7:4, 464–472, DOI: 10.1089/can.2021.0116.
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