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Research on Medical Cannabis and Medical Conditions

Over the past decade, over 30,000 papers about cannabis have been published. While we can’t compile all of them here, we wanted to share some scientific published resources here for you on the use of medical cannabis for different conditions.

Click on a button below to jump to a section or condition you are looking for research on:

Attention-Deficit / Hyperactivity Disorder (ADHD)

1. Cannabis for the Treatment of Attention Deficit Hyperactivity Disorder: A Report of 3 Cases:
We describe 3 patients with ADHD who added cannabis to their treatment regimen and experienced positive therapeutic effects. The improvements in their symptoms and quality of life were substantial, such as the ability to keep emotions in check (3 patients) or to obtain and excel at a new job with more responsibility (2 patients). Objective measures accompanied these narratives with all 3 patients experiencing improvements in validated rating scales for measures of mental health. Scores on the PHQ-9, which measure depression, improved by 8–22 points (30–81%). Improvements on the SCARED, which measure anxiety, ranged from 0 to 27 (up to 33%), and the CEER-9 scale, which indicates emotional regulation, ranged from 2 to 7 (22–78%). Finally, the 9-item SNAP scale measuring inattention showed improvements ranging from 2 to 8 points on the raw scale, which equated to 7–30%. Notably, all 3 patients used cannabis as an adjunct to their other medications (e.g., stimulants, antidepressants, or mood stabilizers). Patient 1 described cannabis as “a really good helping hand” to compliment his other medications. Patient 3 was able to discontinue his stimulant pharmacotherapy, but acknowledged that the “cannabis, in addition to a change in prescription medications to lithium, helped to change his life.” All 3 patients discussed the use of cannabis with their psychiatrist and were authorized oral cannabidiol oil CBD:THC (20:1) from a medical source.


2. Cannabinoid and Terpenoid Doses are Associated with Adult ADHD Status of Medical Cannabis Patients: Participants were adult patients licensed for medical cannabis (MC) treatment who also reported a diagnosis of ADHD by a physician. Data on demographics, ADHD, sleep, and anxiety were collected using self-report questionnaires. Data collected on MC treatment included administration route, cultivator, cultivar name, and monthly dose. The high MC monthly dose group consumed higher levels of most phyto-cannabinoids and terpenes, but that was not the case for all of the cannabis components. The high dose consumers and the ones with lower ASRS score reported a higher occurrence of stopping all ADHD medications. Moreover, there was an association between lower ASRS score subgroup and lower anxiety scores. In addition, we found an association between lower ASRS score and consumption of high doses of cannabinol (CBN), but not with ∆-9-tetrahydrocannabinol (THC). Conclusion: These findings reveal that the higher-dose consumption of MC components (phyto-cannabinoids and terpenes) is associated with ADHD medication reduction. In addition, high dosage of CBN was associated with a lower ASRS score. However, more studies are needed in order to fully understand if cannabis and its constituents can be used for management of ADHD.


1. Clinical outcome data of anxiety patients treated with cannabis-based medicinal products in the United Kingdom: Patients with generalized anxiety disorder (GAD) exhibit sustained improvements in their symptoms following the use of cannabis products. Researchers reported improvements in patients’ anxiety, sleep quality, and overall quality of life at each time point assessed. “Prescription of cannabis-based medicinal products in those with Generalized Anxiety Disorder is associated with clinically significant improvements in anxiety with an acceptable safety profile in a real-world setting,” they concluded.

2. Cannabidiol in Anxiety and Sleep: A Large Case Series: Evidence points toward a calming effect for CBD in the central nervous system. A large retrospective case series at a psychiatric clinic involving clinical application of CBD for anxiety and sleep complaints as an adjunct to usual treatment. The retrospective chart review included monthly documentation of anxiety and sleep quality in 103 adult patients. The final sample consisted of 72 adults presenting with primary concerns of anxiety (n = 47) or poor sleep (n = 25). Anxiety scores decreased within the first month in 57 patients (79.2%) and remained decreased during the study duration. Sleep scores improved within the first month in 48 patients (66.7%) but fluctuated over time. In this chart review, CBD was well tolerated in all but 3 patients.


1. Cannabidiol as a treatment for arthritis and joint pain: an exploratory cross-sectional study: A novel anonymous questionnaire was created to evaluate perceived efficacy of cannabidiol for the treatment of arthritis. A self-selected convenience sample (N=428) was recruited through online methods including social media accounts and newsletters (The Arthritis Foundation and Savvy Cooperative) between May 5, 2020, and November 5, 2020. Statistical analysis was performed to determine differences between types of arthritis and improvements in quality-of-life symptoms. Furthermore, a regression analysis was performed to identify variables associated with decreasing or discontinuing other medications. CBD use was associated with improvements in pain (83%), physical function (66%), and sleep quality (66%). Subgroup analysis by diagnosis type (osteoarthritis, rheumatoid, or other autoimmune arthritis) found improvements among groups for physical function (P=0.013), favoring the osteoarthritis group. The overall cohort reported a 44% reduction in pain after CBD use (P<0.001). The osteoarthritis group had a greater percentage reduction (P=0.020) and point reduction (P<0.001) in pain compared to rheumatoid arthritis and other autoimmune arthritis. The majority of respondents reported a reduction or cessation of other medications after CBD use (N=259, 60.5%): reductions in anti-inflammatories (N=129, 31.1%), acetaminophen (N=78, 18.2%), opioids (N=36, 8.6%) and discontinuation of anti-inflammatories (N=76, 17.8%), acetaminophen (N=76, 17.8%), and opioids (N=81, 18.9%).

2. Cannabis and Rheumatoid Arthritis: A Scoping Review Evaluating the Benefits, Risks, and Future Research Directions: Preclinical in vitro and in vivo studies show promising results regarding the anti-arthritic properties of cannabinoids, psychoactive and non-psychoactive cannabinoids alike. These anti-arthritic properties are mediated by anti-inflammatory effects of cannabinoids, including inhibiting the production of pro-inflammatory cytokines and nitric oxide, as well as the proliferation of synovial fibroblasts.

3. Your Most Common Medical Cannabis Questions From Arthritis Patients Answered: While this isn’t a published paper, it is a great resource. Having assisted thousands of patients diagnosed with both rheumatoid and osteoarthritis at our clinics, we wanted to share some of the most common questions we get, ensuring you have answers you may be looking for.

Autism Spectrum Disorder (ASD)

1. Individually tailored dosage regimen of full-spectrum Cannabis extracts for autistic core and comorbid symptoms: a real-life report of multi-symptomatic benefits: Autistic life quality rose in rare study of customized cannabis treatments. Many caretakers reported improvements in co-morbidities and symptoms like seizures (84%), emotional meltdowns (76%), discomfort in noisy or crowded places (72%), aggression toward others (67%), eating non-foods (63%), excessive appetite (62%) and making screams and random sounds (54%). Cannabis also appeared to consistently improve communication-related abilities—85% of caretakers reported that their autistic loved one was more receptive to direct verbal communication. Furthermore, 75% reported improvement to visual contact and attention to conversation; verbal communication improved for 50% of patients. Still, the study suggests that larger, double-blind studies are warranted and may give us more insight into how cannabis impacts autistic patients. Additionally, it sheds light on how different patients might respond better to different doses and ratios of CBD to THC—and how to approach this challenge clinically. This insight could shift how future research on autism and cannabis is carried out, and yield more accurate results about its potential benefits.

2. Children and adolescents with ASD treated with CBD-rich cannabis exhibit significant improvements particularly in social symptoms: an open label study: An exciting study from Translational Psychiatry about Children with autism spectrum disorder shows improvement after being treated with cannabidiol (CBD)-rich medicinal cannabis. The report showed a significant improvement in their social communication abilities and a reduction in restrictive and repetitive behaviours. “Children with autism spectrum disorders reported significant improvements in their social communication abilities after six months of treatment with CBD-rich cannabis oil.” 


1. Medical cannabis is effective for cancer-related pain: Quebec Cannabis Registry results: A study done at the McGill University Health Centre has concluded that medical cannabis has a complementary role to play in fighting cancer pain. It also found the use of cannabis would help reduce the total number of medications and opioids taken by patients. After three months, Dr. Antonio Vigano’s team said they saw “clinically significant reductions in pain scores in patients.” These reductions persisted for a year, and the patients were able to gradually reduce their use of pain medication. The researchers recruited 358 adult cancer patients for their study. The average age of the patients was 57, and about half of them were men. The most common cancer diagnoses were genitourinary and breast cancers, followed by bowel, lung and blood cancers. The study also found that products with a balance between the active ingredients tetrahydrocannabinol (THC) and cannabidiol (CBD), rather than a dominance of one or the other, seem to be more effective.

2. Cannabis use in cancer patients: acute and sustained associations with pain, cognition, and quality of life: This observational study is among the first of its kind to examine associations between legal market, palliative cannabis use, and subjective and objective outcomes among cancer patients. These early findings concerning pain intensity, sleep quality, and cognitive function can help to inform future, fully powered studies of this important topic. ​​Twenty-five participants [mean (standard deviation, SD) age = 54.3 years (15.6); 13 females (52.0%)] completed all study appointments and were included in the analysis. Sustained cannabis use was associated with improvements in pain intensity, pain interference, sleep quality, subjective cognitive function, and reaction times in the Stroop task, but no change in general quality of life was observed. High levels of cannabidiol (CBD) use during the two-week ad libitum use period was associated with steeper improvements in pain intensity and sleep quality. Participants reported improvements in pain intensity and increased feelings of subjective high after acute use. High levels of Δ9-tetrahydrocannabinol (THC) use during the acute administration appointment was associated with steeper increases in feelings of subjective high. Improvements in pain were associated with improvements in subjective cognitive function.

3. Cannabinoids in cancer treatment: Therapeutic potential and legislation: Cannabinoids are a large and important class of complex compounds that have a promising therapeutic potential for the treatment of variety of diseases, including cancer. In this review, we focused on studies that provided evidence for anticancer effects of plant-derived and synthetic cannabinoids and their potential mechanisms of action. Cannabinoids were able to effectively modulate tumor growth in different in vitro and in vivo cancer models, however, these anticancer effects appears to be dependent on cancer type and drug dose. Understanding how cannabinoids are able to modulate essential cellular processes involved in tumorigenesis, such as the progression through the cell cycle, cell proliferation and cell death, as well as the interactions between cannabinoids and immune system are crucial for improving existing medications and developing new therapeutic approaches.

4. The endogenous cannabinoid, anandamide, induces cell death in colorectal carcinoma cells: a possible role for cyclooxygenase: These findings suggest anandamide may be a useful chemopreventive/therapeutic agent for colorectal cancer as it targets cells that are high expressors of COX-2, and may also be used in the eradication of tumour cells that have become resistant to apoptosis.

5. The cannabinoid delta(9)-tetrahydrocannabinol inhibits RAS-MAPK and PI3K-AKT survival signalling and induces BAD-mediated apoptosis in colorectal cancer cells: There is emerging evidence that cannabinoids, especially Delta(9)-tetrahydrocannabinol (THC), may represent novel anticancer agents, due to their ability to regulate signalling pathways critical for cell growth and survival. Here, we report that CB1 and CB2 cannabinoid receptors are expressed in human colorectal adenoma and carcinoma cells, and show for the first time that THC induces apoptosis in colorectal cancer cells. These data suggest an important role for CB1 receptors and BAD in the regulation of apoptosis in colorectal cancer cells. The use of THC, or selective targeting of the CB1 receptor, may represent a novel strategy for colorectal cancer therapy.

6. Endocannabinoids as emerging suppressors of angiogenesis and tumor invasion (review): There is increasing evidence that endocannabinoids are able to inhibit cancer cell growth in culture as well as in animal models. Most work has focused on the role of endocannabinoids in regulating tumor cell growth and apoptosis and ongoing research is addressed to further dissect the precise mechanisms of cannabinoid antitumor action. However, endocannabinoids are now emerging as suppressors of angiogenesis and tumor spreading since they have been reported to inhibit angiogenesis, cell migration and metastasis in different types of cancer, pointing to a potential role of the endocannabinoid system as a target for a therapeutic approach of such malignant diseases. The potential use of cannabinoids to retard tumor growth and spreading is even more appealing considering that they show a good safety profile, regarding toxicity, and are already used in cancer patients as palliatives to stimulate appetite and to prevent devastating effects such as nausea, vomiting and pain.

7. Anti-Cancer Potential of Cannabinoids, Terpenes, and Flavonoids Present in Cannabis: Cannabinoids have been suggested and shown to be effective in the treatment of various conditions. In cancer, the endocannabinoid system is altered in numerous types of tumours and can relate to cancer prognosis and disease outcome. Additionally, cannabinoids display anticancer effects in several models by suppressing the proliferation, migration and/or invasion of cancer cells, as well as tumour angiogenesis. However, the therapeutic use of cannabinoids is currently limited to the treatment of symptoms and pain associated with chemotherapy, while their potential use as cytotoxic drugs in chemotherapy still requires validation in patients. Along with cannabinoids, cannabis contains several other compounds that have also been shown to exert anti-tumorigenic actions. The potential anti-cancer effects of cannabinoids, terpenes and flavonoids, present in cannabis, are explored in this literature review.

8. Cannabinoid-induced cell death in endometrial cancer cells: involvement of TRPV1 receptors in apoptosis: These data indicate that cannabinoids modulate endometrial cancer cell death. Selective targeting of TPRV1 by AEA, CBD, or other stable analogues may be an attractive research area for the treatment of estrogen-dependent endometrial carcinoma. Our data further support the evaluation of CBD and CBD-rich extracts for the potential treatment of endometrial cancer, particularly, that has become non-responsive to common therapies.

Chronic Pain

1. Medical Cannabis for the Management of Pain and Quality of Life in Chronic Pain Patients: A Prospective Observational Study: Apollo’s published research study had a total of 751 chronic pain patients who initiated medical cannabis treatment at Apollo Cannabis Clinics. After following Apollo’s personalized treatment plan, patients reported a 43% reduction in pain interference with their daily activities and a 37% reduction in the severity of their pain. The patients in the study also reported significant improvements in mental health after initiating treatment.

2. Clinical outcome data of chronic pain patients treated with cannabis-based oils and dried flower: Chronic pain patients who use cannabis products for six months report improvements in their health-related quality of life and decreases in their daily opioid consumption. British investigators assessed the safety and efficacy of plant-derived cannabis products (either oils, flower, or a combination of both) in over 700 chronic pain patients. “Treatment with oil-based [products], dried flowers, or a combination of both CBMPs [cannabis-based medicinal products] are associated with statistically significant improvements in pain relief and sleep quality after six months in chronic pain patients. Additionally, patients prescribed oils or both types of CBMPs experienced reduced anxiety and an improvement in their ability to perform daily activities. Patients prescribed a combination of both CBMPs recorded improvements in their self-care and mobility abilities.

Concussions / Traumatic Brain Injuries (TBI)

1. Cannabidiol’s neuroprotective properties and potential treatment of traumatic brain injuries: Via a variety of targets, CBD appears to reduce cognitive (changes in memory, attention, and mood) and physiological symptoms associated with TBI, and lessen TBI-induced nociception.

2. Cannabinoids in traumatic brain injury and related neuropathologies: preclinical and clinical research on endogenous, plant-derived, and synthetic compounds: The endocannabinoid system is increasingly recognized for its physiological role in regulating cellular activity in the brain and endogenous response to adverse events, such as TBI. The ability to modulate this system with endogenous, plant-derived, or synthetic cannabinoids is promising for the development of therapeutic strategies for TBI.  Presently, the strongest evidence for neuroprotective properties is seen for compounds containing CBD, or those targeting CB2R, and the effects of THC treatment are less consistent. CBG (and its derivatives) is the most studied minor phytocannabinoid in neurological disease models, while the most evidence for therapeutic benefit from terpenes relates to BCP, although studies are limited overall. The evidence for a modulating, or even synergistic ‘entourage’ effect when cannabinoids are used in combination is still emerging, but full-spectrum plant extracts with a variety of phytocannabinoids may improve the safety and therapeutic profile of cannabinoid medicine.

3. Effect of marijuana use on outcomes in traumatic brain injury: Traumatic brain injury (TBI) is associated with significant morbidity and mortality. Several studies have demonstrated neuroprotective effects of cannabinoids. The objective of this study was to establish a relationship between the presence of a positive toxicology screen for tetrahydrocannabinol (THC) and mortality after TBI. A 3-year retrospective review of registry data at a Level I center of patients sustaining TBI having a toxicology screen was performed. Pediatric patients (younger than 15 years) and patients with a suspected nonsurvivable injury were excluded. The THC(+) group was compared with the THC(-) group with respect to injury mechanism, severity, disposition, and mortality. Logistic regression was used to determine independent associations with mortality. There were 446 cases meeting all inclusion criteria. The incidence of a positive THC screen was 18.4 per cent (82). Overall mortality was 9.9 per cent (44); however, mortality in the THC(+) group (2.4% [two]) was significantly decreased compared with the THC(-) group (11.5% [42]; P = 0.012). After adjusting for differences between the study cohorts on logistic regression, a THC(+) screen was independently associated with survival after TBI (odds ratio, 0.224; 95% confidence interval, 0.051 to 0.991; P = 0.049). A positive THC screen is associated with decreased mortality in adult patients sustaining TBI.

Crohn's Disease & Ulcerative Colitis (Inflammatory Bowel Diseases) (IBD & IBS)

1. The effect of medical cannabis in inflammatory bowel disease: British investigators assessed the safety and efficacy of cannabis products in 76 patients diagnosed with either Crohn’s disease or ulcerative colitis. Each of them possessed a doctor’s authorization to consume cannabis. Study participants consumed either cannabis extracts, THC-dominant flowers, or both for a period of three months. Authors reported: “Initiation of CBMPs [cannabis-based medicinal products] was associated with an improvement in HRQoL [health-related quality of life] in the short term, with statistically significant improvements in IBD-specific and general HRQoL outcomes at 1 and 3 months after initiating treatment. Participants who previously consumed cannabis had greater improvements in HRQoL and fewer adverse events compared to naïve individuals. These findings highlight the potential utility of CBMPs as an adjunctive therapeutic option in the short term, especially in patients who continue to experience debilitating symptoms despite maximal medical therapy.” Longitudinal data from Israel has similarly reported that the long-term use of whole-plant cannabis is associated with both symptom improvement and the reduced use of prescription medications in patients with treatment-resistant inflammatory bowel disease.

2. Cannabinoid Receptor-2 Ameliorates Inflammation in Murine Model of Crohn’s Disease: The study identified a distinct anti-inflammatory role played by the CB2 receptors of the ECS that results in positive outcomes for patients suffering Crohn’s, IBD, and other disease of the gut involving inflammation. “Cannabinoid receptor stimulation may have positive symptomatic effects on inflammatory bowel disease [IBD] patients through analgesic and anti-inflammatory effects,” reported the study. While only involving rodents, the study concluded that the human endocannabinoid system plays a valuable role in controlling inflammation and inflammatory responses. “The compilation of past evidence and our current results validate the ECS as a promising therapeutic target in inflammatory conditions such as IBD” reported the scientists.

Dementia & Alzheimer's Disease

1. Effects of rich cannabidiol oil on behavioral disturbances in patients with dementia: A placebo controlled randomized clinical trial: In this randomized, double-blind, single-cite, placebo-controlled trial, patients aged at least 60, with a diagnosis of major neurocognitive disorder and associated behavioral disturbances were randomized 2:1 to receive either a broad-spectrum cannabis oil (30% cannabidiol and 1% tetrahydrocannabinol: 295 mg and 12.5 mg per ml, respectively; n = 40) or a placebo oil (n = 20) three times a day for 16 weeks. The primary outcome was a decrease, as compared to baseline, of four or more points on the Cohen-Mansfield Agitation Inventory score by week 16.

2. Cannabinoids remove plaque-forming Alzheimer’s proteins from brain cells: Scientists have found preliminary evidence that tetrahydrocannabinol (THC) and other compounds found in marijuana can promote the cellular removal of amyloid beta, a toxic protein associated with Alzheimer’s disease.

3. Cannabinoids for Agitation in Alzheimer’s Disease: Cannabinoids require further investigation, but show promising preliminary results for mitigating the damaging consequences of agitation and aggression in AD.

4. Assessing Cannabidiol as a Therapeutic Agent for Preventing and Alleviating Alzheimer’s Disease Neurodegeneration: Researchers from China Pharmaceutical University in Nanjing discovered that cannabidiol (CBD), a key cannabis compound without intoxicating effects like THC, might enhance cognitive function and potentially offer protection against Aβ42, a protein derived from the amyloid precursor protein, which is a noteworthy biomarker associated with Alzheimer’s disease onset, mild cognitive impairment, vascular dementia, and other cognitive disorders. In Alzheimer’s brains, cells gather around clumps known as amyloid plaques to clear them, but these plaques cause inflammation, damaging nerve cell connections, leading to cell death, and affecting memory. The study examined in vitro if CBD could reduce this inflammation in mice treated with Aβ1–42. Results showed CBD significantly lowered inflammatory agents, reduced microglia activation, and lessened astrocyte activation in critical brain regions affected by Aβ-stimulation.


1. Assessment of clinical outcomes of medicinal cannabis therapy for depression: British investigators assessed the safety and efficacy of cannabis products in 129 subjects with a primary diagnosis of depression. Study subjects all possessed a doctor’s authorization to consume cannabis. Study participants consumed either cannabis extracts, THC-dominant flowers, or both for a period of six-months. Researchers reported: “The results showed that medicinal cannabis was associated with improvements in depression and anxiety symptoms, as well as health-related quality of life, and sleep quality after 1, 3, and 6 months of treatment.” While some subjects reported adverse events from cannabis products, almost all side effects were classified as either “mild or moderate.”

2. Medical cannabis use in Canada and its impact on anxiety and depression: A retrospective study: There were 7,362 patients included in the sample, of which the average age was 49.8 years, and 53.1% were female. There were statistically significant improvements between baseline and follow-up scores for both the GAD-7 and PHQ-9, with larger improvements seen for patients who were actively seeking medical cannabis to treat anxiety or depression. From 12 months on, those reporting anxiety had an average decrease in GAD-7 scores that was greater than the minimum clinically important difference of 4, and the same was seen for patients reporting depression from 18 months on, with the average decrease in PHQ-9 scores more than the MCID minimum clinically important difference of 5. This study provides some evidence to support the effectiveness of medical cannabis as a treatment for anxiety and depression.

3. Effectiveness of Medical Cannabis for the Treatment of Depression: A Naturalistic Outpatient Study: Patients were 20-54 years old; 72.9% were male; one third reported times of regular cannabis consumption within the previous five years. Mean severity of depression decreased from 6.9 points (SD 1.5) at entry to 3.8 points (2.7) at week 18. A treatment response (>50% reduction of the initial score) was seen in 50.8% at week 18. One third of patients complained about side effects, none was considered as severe. Concomitant antidepressant medication (31% of patients) was not associated with outcome. Conclusions: Medical cannabis was well tolerated and dropout rate was comparable to those in clinical trials of antidepressant medication. Patients reported a clinically significant reduction of depression severity. Further research on the effectiveness of medical cannabis for MDD seems warranted. Risks of this medication, such as sustaining or inducing a cannabis use disorder, or side effects such as poor concentration, must be taken into consideration.


1. Endocannabinoid involvement in endometriosis: Here, using a rat model, we found that CB1 cannabinoid receptors are expressed on both the somata and fibers of both the sensory and sympathetic neurons that innervate endometriosis’s abnormal growths. We further found that CB1 receptor agonists decrease, whereas CB1 receptor antagonists increase, endometriosis-associated hyperalgesia. Together these findings suggest that the endocannabinoid system contributes to mechanisms underlying both the peripheral innervation of the abnormal growths and the pain associated with endometriosis, thereby providing a novel approach for the development of badly-needed new treatments.

2. Cannabis Use, a Self-Management Strategy Among Australian Women With Endometriosis: Results From a National Online Survey: A total of 484 responses were included for analysis, with 76% of the women reporting the use of general self-management strategies within the last 6 months. Of those using self-management, 13% reported using cannabis for symptom management. Self-reported effectiveness in pain reduction was high (7.6 of 10), with 56% also able to reduce pharmaceutical medications by at least half. Women reported the greatest improvements in sleep and in nausea and vomiting. Adverse effects were infrequent (10%) and minor.


1. Epilepsy and Cannabis: A Literature Review: In contrast, more recent studies that have included over 100 participants showed that CBD use resulted in a significant reduction in seizure frequency. Adverse effects of CBD overall appear to be benign, while more concerning adverse effects (e.g., elevated liver enzymes) improve with continued CBD use or dose reduction.

2. CBD-enriched medical cannabis for intractable pediatric epilepsy: The current Israeli experience: CBD treatment yielded a significant positive effect on seizure load. Most of the children (66/74, 89%) reported reduction in seizure frequency: 13 (18%) reported 75–100% reduction, 25 (34%) reported 50–75% reduction, 9 (12%) reported 25–50% reduction, and 19 (26%) reported <25% reduction. Five (7%) patients reported aggravation of seizures which led to CBD withdrawal. In addition, we observed improvement in behavior and alertness, language, communication, motor skills and sleep. Adverse reactions included somnolence, fatigue, gastrointestinal disturbances and irritability leading to withdrawal of cannabis use in 5 patients.


1. Adding medical cannabis to standard analgesic treatment for fibromyalgia: a prospective observational study: The researchers recruited just over a hundred patients at the Luigi Sacco University Hospital in Milan, Italy. Sixty-six of them were interviewed over six months of treatment. The average participant was 52 years old, and over 90% of sufferers were women (women make up the vast majority of people with fibromyalgia). The study focused on treating refractory patients – meaning people who are stably taking medications, but haven’t found relief. Just under half of their patients were taking two other drugs, while nearly a third took at least three. These drugs were severe central sedatives, including opioids, anti-convulsants, nerve blockers, and anti-depressants. Given the intensity of the drugs people were already taking, it was astounding to find that half of patients (47%) got enough relief from cannabis to reduce or cease their painkiller usage. Between a third and half of the patients experienced notable benefits with respect to sleep, anxiety, depression, and pain symptoms.

2. Cannabis for the Treatment of Fibromyalgia: A Systematic Review: The results of four randomized controlled trials (RCTs) and five observational studies (a total of 564 patients) that investigated the effects of cannabis on fibromyalgia symptoms were included in this review. Of the RCTs, only one demonstrated that cannabinoids did not have a different effect than placebo on pain responses. Overall, this analysis shows low-quality evidence supporting short-term pain reduction in people with fibromyalgia treated with cannabinoid therapeutics. Although current evidence is limited, medical cannabis appears to be a safe alternative for treating fibromyalgia.

Menstrual Pain / PMS

1. Cannabis and symptoms of PMS and PMDD: Cannabis has been found to alleviate a wide array of medical symptoms, including those that overlap with physical and emotional symptoms of premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD), including insomnia, irritability, depression, and joint pain. Little work has addressed the use of cannabis as a treatment for PMS or PMDD or the role of women’s cannabis treatment expectancies as a predictor of consumption. Women who reported having experienced PMS and PMDD and endorsed lifetime cannabis use (N = 145), completed an online survey assessing their frequency of cannabis use, PMS/PMDD symptoms, expectancies of cannabis-induced relief from symptoms, as well as cannabis-related problems. Women were found to hold meaningful expectancies that cannabis would treat all PMS/PMDD symptoms, except for overeating/food cravings.


1. A survey of medical cannabis use during perimenopause and postmenopause: “Results suggest that many individuals are currently using MC as an adjunctive treatment for menopause-related symptoms, particularly sleep disturbance and mood/anxiety. Increased severity and prevalence of mood and anxiety symptoms in perimenopausal participants suggest promising targets for clinical trials of cannabinoid-based therapies.”


1. Medical Cannabis for the Treatment of Migraine in Adults: A Review of the Evidence: There are a handful of trustworthy, clinical, and peer-reviewed studies surfacing on the use of cannabis and cannabinoids for migraines, many published in recent years. “Medical Cannabis for the Treatment of Migraine in Adults: A Review of the Evidence” reviewed 12 publications and 1,980 participants in both Italy and the United States in May of 2022. Its researchers led by Dr. Babasola O Okusanya found that “medical cannabis significantly reduced nausea and vomiting associated with migraine attacks after 6 months of use.” It also found that cannabis reduced the number of days of migraine after 30 days, and the frequency of migraine headaches per month. They found medical cannabis reduced migraine headaches per month from 10.4 to 4.6 at follow-up. It also found medical cannabis eliminated migraines in 11.6% of users.

2. Use of Vaporized Cannabis as a Potential Treatment for Migraine: A double-blind, placebo-controlled, crossover, randomized controlled trial of vaporized cannabis as a potential acute treatment of migraine. Conducted from November 2020 to February 2023, patients were randomly assigned to either tetrahydrocannabinol (THC) 6%, a mix of THC and cannabinoid (CBD) 11%, CBD 11%, and placebo cannabis. Patients underwent at least a 1-week washout period between treated migraine attacks. At the conclusion of the trial, 4 puffs of vaporized THC/CBD mix flower was efficacious for acute migraine treatment, showing impacts on 2 hour pain relief and freedom, as well as resolution of most bothersome symptom 2 hours after migraine attack. “The doses that we used are probably lower than what a lot of people out there are using on their own, and higher doses does not necessarily mean more effective.”

Multiple Sclerosis (MS)

1. The Efficacy of Cannabis on Multiple Sclerosis-Related Symptoms: The efficacy of Cannabis sativa (C. Sativa) in the management of MS outcomes such as spasticity, pain, tremors, ataxia, bladder functions, sleep, quality of life, and adverse effects were assessed in this review. Most clinical studies showed the positive effects of cannabinoids with their different routes of administration, such as oromucosal spray and oral form, in reducing most MS symptoms. The oromucosal spray Nabiximols demonstrated an improvement in reducing MS spasticity, pain, and quality of life with a tolerated adverse effect. Oral cannabinoids are significantly effective for treating MS pain and spasticity, while the other symptoms indicate slight improvement and the evidence is quite inconsistent. Oromucosal spray and oral cannabis are mainly used for treating patients with MS and have positive effects on treating the most common symptoms of MS, such as pain and spasticity, whereas the other MS symptoms indicated slight improvement, for which further studies are needed.

2. Medical cannabis use in Canadians with multiple sclerosis: This study showed that nearly two-thirds of survey respondents, comprised of Canadians living with MS, have tried medical cannabis at least once and that those with a greater disease burden were more likely to have tried it. Users reported that cannabis is moderately to highly effective in treating several symptoms and that adverse effects are not generally severe, nor are they the main factor driving medical cannabis cessation. Our results support the need for more research examining medical cannabis use in MS and for evidence-based resources to be publicly available for those exploring it as a potential therapy. Completed questionnaires were submitted by 344 individuals. Among respondents, 215/344 (64.5%) reported having used medical cannabis at least once, and 180 (52.3%) reported still currently using it. Based on disease and quality of life data, we found that respondents with more severe or progressive forms of MS were more likely to have tried medical cannabis. Medical cannabis was used most by current and former users to treat sleep problems (84.2%), pain (80.0%), and spasticity (68.4%), while the most reported adverse effects were drowsiness (57.2%), feeling quiet/subdued (48.8%), and difficulty concentrating (28.4%).


1. Regulation of nausea and vomiting by cannabinoids: Considerable evidence demonstrates that manipulation of the endocannabinoid system regulates nausea and vomiting in humans and other animals. The anti-emetic effect of cannabinoids has been shown across a wide variety of animals that are capable of vomiting in response to a toxic challenge. Recently, evidence from animal experiments suggests that cannabinoids may be especially useful in treating the more difficult to control symptoms of nausea and anticipatory nausea in chemotherapy patients, which are less well controlled by the currently available conventional pharmaceutical agents.

2. The Effectiveness of Common Cannabis Products for Treatment of Nausea: By 1 hour postconsumption, 96.4% of people had experienced symptom relief with an average symptom intensity reduction of -3.85 points on a 0 to 10 visual analog scale (SD=2.45, d=1.85, P<0.001). Symptom relief was statistically significant at 5 minutes and increased with time. Among product characteristics, flower and concentrates yielded the strongest, yet similar results; products labeled as Cannabis indica underperformed those labeled as Cannabis sativa or hybrid; and joints were associated with greater symptom relief than pipes or vaporizers. In sessions using flower, higher tetrahydrocannbinol and lower cannabidiol were generally associated with greater symptom relief (eg, within 5 min).


1. Managing the symptoms of Parkinson’s Disease with medical cannabis: Exploring the patient perspective: Patient questionnaires reveal that some Parkinson’s disease patients are managing their own symptoms with medical cannabis, with reported improvements in symptoms. Nancy Cross, Analyst at Lightning Health takes a look at the power of the patient perspective and its importance in increasing the understanding of the potential benefits associated with medical cannabis. These studies are important to better understand patients’ knowledge, experience and perceptions of using cannabis for Parkinson’s. Fears around side effects and addiction, lack of evidence, stigma and discouragement from healthcare teams were all identified as barriers to use for PD patients. In those patients that self-reported as cannabis users, many reported an improvement in their Parkinson’s symptoms in both the German and U.S. studies. 41% and 42.9% of users in the U.S. reported improvement in motor symptoms and non-motor symptoms. The two studies revealed that patients perceived an improvement in depression or anxiety, pain, sleep disorders, stiffness, and tremors or muscle cramps with cannabis use.

Nerve Pain

1. Smoked cannabis for chronic neuropathic pain: a randomized controlled trial: Adults with post-traumatic or postsurgical neuropathic pain were randomly assigned to receive cannabis at four potencies (0%, 2.5%, 6% and 9.4% tetrahydrocannabinol) over four 14-day periods in a crossover trial. We recruited 23 participants (mean age 45.4 [standard deviation 12.3] years, 12 women [52%]), of whom 21 completed the trial. A single inhalation of 25 mg of 9.4% tetrahydrocannabinol herbal cannabis three times daily for five days reduced the intensity of pain, improved sleep and was well tolerated.

2. Cannabis analgesia in chronic neuropathic pain is associated with altered brain connectivity: Fifteen patients with chronic radicular neuropathic pain participated in a randomized, double-blind, placebo-controlled trial employing a counterbalanced, within-subjects design. Pain assessments and functional resting state brain scans were performed at baseline and after sublingual THC administration. We examined functional connectivity of the anterior cingulate cortex (ACC) and pain-related network dynamics using graph theory measures. THC significantly reduced patients’ pain compared to placebo. THC-induced analgesia was correlated with a reduction in functional connectivity between the anterior cingulate cortex (ACC) and the sensorimotor cortex. Moreover, the degree of reduction was predictive of the response to THC.


1. Cannabis-Based Products for the Treatment of Skin Inflammatory Diseases: A Timely Review: Some cannabinoids may help treat dermatological diseases such as psoriasis, eczema and acne. Many minor cannabinoids exhibit anti-inflammatory, analgesic, antimicrobial, and anti-itch properties.

2. Topical cannabinoids may help to treat skin diseases: Cannabinoids – a class of chemicals found in cannabis – may be effective as a topical treatment for an array of skin diseases, including psoriasis, severe itching, and atopic and contact dermatitis. This is the conclusion of a new review by researchers from the University of Colorado.

Post Traumatic Stress Disorder (PTSD)

1. Assessment of clinical outcomes in patients with post-traumatic stress disorder: analysis from the UK Medical Cannabis Registry: British investigators assessed the safety and efficacy of cannabis products in 162 PTSD patients with a physician’s authorization. Study participants consumed either cannabis extracts or THC-dominant flowers for a period of six-months. Authors reported that patients showed “statistically significant improvements” in a variety of domains, including sleep, anxiety, and stress. Self-reported adverse events were typically mild in severity. “This observational study suggests an association between CBMP [cannabis-based medicinal products] treatment and improvement in PTSD-specific, HRQoL [health-related quality of life], sleep, and anxiety outcomes at up to 6-month follow-up,”.

2. Medical cannabis for treatment-resistant combat PTSD: All participants were relatively mature (mean age was 50 years old), treatment-resistant, chronic combat-PTSD patients who had undergone several pharmacological treatment lines and prolonged exposure therapy prior to receiving treatment with cannabis, and were treated in the same clinic by the same expert psychiatrist in the field of PTSD (NN). Prior to treatment with cannabis, patients continued to suffer from moderate to high-level PTSD symptoms despite being in treatment for an average of 7 years. In addition, the study’s uniqueness is also in the long follow-up of patients, averaging over a year (range 0.5-3 years), enabling the assessment of the effect of cannabis on PTSD symptoms, possible side effects, and the possibility of addiction. The study’s findings show an overall improvement in sleep quality and duration, as well as a decrease in PTSD symptoms. According to the PDS questionnaire, there was a reduction of at least 20% in PTSD symptoms in over 65% of patients, with nearly 80% showing improvement. Surprisingly, unlike other studies, the decrease in nightmares was observed but was not significant, maybe due to the small number of participants.

3. Cannabinoid modulation of corticolimbic activation to threat in trauma-exposed adults: a preliminary study: Excessive fear and anxiety, coupled with corticolimbic dysfunction, are core features of stress- and trauma-related psychopathology, such as posttraumatic stress disorder (PTSD). Interestingly, low doses of ∆9-tetrahydrocannabinol (THC) can produce anxiolytic effects, reduce threat-related amygdala activation, and enhance functional coupling between the amygdala and medial prefrontal cortex and adjacent rostral cingulate cortex (mPFC/rACC) during threat processing in healthy adults. Together, these findings suggest the cannabinoid system as a potential pharmacological target in the treatment of excess fear and anxiety. Using a randomized, double-blind, placebo-controlled, between-subjects design, 71 participants were randomly assigned to receive either THC or placebo (PBO) and subsequently completed a well-established threat processing paradigm during functional magnetic resonance imaging. In adults with PTSD, THC lowered threat-related amygdala reactivity, increased mPFC activation during threat, and increased mPFC-amygdala functional coupling. These preliminary data suggest that THC modulates threat-related processing in trauma-exposed individuals with PTSD, which may prove advantageous as a pharmacological approach to treating stress- and trauma-related psychopathology.

4. Effects of ∆9-tetrahydrocannabinol on aversive memories and anxiety: a review from human studies: Here, we seek to review and discuss the effects of THC on aversive memory extinction and anxiety in healthy humans and PTSD patients. At low doses, THC can enhance the extinction rate and reduce anxiety responses.

Reductions in Opioids and Pharmaceuticals

1. Medical Cannabis for the Management of Pain and Quality of Life in Chronic Pain Patients: A Prospective Observational Study: Apollo’s published research study had a total of 751 chronic pain patients who initiated medical cannabis treatment at Apollo Cannabis Clinics. After following Apollo’s personalized treatment plan, patients reported a 43% reduction in pain interference with their daily activities and a 37% reduction in the severity of their pain. The patients in the study also reported significant improvements in mental health after initiating treatment.

2. Perceived Effectiveness of Medical Cannabis Among Adults with Chronic Pain: Findings from Interview Data in a Three-Month Pilot Study: Another study has linked medical marijuana use to lower pain levels and reduced dependence on opioids and other prescription medications. Researchers at the University of Florida carried out a three-month pilot study to assess the efficacy of cannabis among middle-aged and older chronic pain patients. The benefits that they reported include reduced pain and anxiety, improved physical and mental functioning, better sleep quality and mood and less reliance on prescription medications, including opioids and benzodiazepines.

3. Changes in Prescribed Opioid Dosages Among Patients Receiving Medical Cannabis for Chronic Pain: The analysis looked at data from more than 8,000 patients registered in New York’s medical cannabis program, tracking how their opioid prescriptions changed over time. It concluded that among pain patients who received marijuana for more than 30 days, opioid amounts fell by nearly half.

4. Clinical outcome data of chronic pain patients treated with cannabis-based oils and dried flower: Chronic pain patients who use cannabis products for six months report improvements in their health-related quality of life and decreases in their daily opioid consumption. British investigators assessed the safety and efficacy of plant-derived cannabis products (either oils, flower, or a combination of both) in over 700 chronic pain patients. “Treatment with oil-based [products], dried flowers, or a combination of both CBMPs [cannabis-based medicinal products] are associated with statistically significant improvements in pain relief and sleep quality after six months in chronic pain patients. Additionally, patients prescribed oils or both types of CBMPs experienced reduced anxiety and an improvement in their ability to perform daily activities. Patients prescribed a combination of both CBMPs recorded improvements in their self-care and mobility abilities.

5. Cannabis use to manage opioid cravings among people who use unregulated opioids during a drug toxicity crisis: “This study has found that marijuana is “significantly” associated with reduced opioid cravings for people using them without a prescription, suggesting that expanding access to legal cannabis could provide more people with a safer substitute. 58 percent of participants reported that their motivation to use marijuana was to reduce opioid cravings. And a multivariable analysis showed that cannabis use “was significantly associated with self-reported reductions in opioid use.”

Sleep Disorders (Insomnia)

1. A large-scale survey of cannabis use for sleep: preferred products and perceived effects in comparison to over-the-counter and prescription sleep aids: Compared to using conventional sleep aids or no sleep aids at all, respondents reported that cannabis made them feel more refreshed, focused and better able to function the morning after, with fewer headaches and less nausea. In general, the use of cannabis for sleep-related issues was perceived as more advantageous than over-the-counter medications or prescription sleep aids. But they also reported some side effects from use, including waking up feeling sleepy, anxious and irritable. The WSU researchers surveyed 1,216 people for the study. Nearly two thirds (64.9 percent) of participants reported that they’d been suffering from sleep issues for at least five years, while nearly 70 percent said they’d been using cannabis to help with sleep for at least a year. A plurality of respondents (38 percent) said they’d been using marijuana for sleep for between one and three years. Asked to report how cannabis helps with their sleep, respondents said it relaxed their body (81.0 percent) and mind (83.0 percent), helped prevent interruptions in sleep (36.3 percent) and promoted a deeper (56.2 percent), longer (41.6 percent) sleep.

2. Cannabis use in patients with insomnia and sleep disorders: Retrospective chart review: A retrospective chart review found that lower doses of THC can help with: Reducing sleep onset latency, Greater ease of falling asleep, Increased slow-wave sleep, & Increased total sleep time. Cannabis, specifically with strains containing higher levels of THC, is known to have a dose-dependent effect on sleep. THC acts on the CB1 receptors in the central nervous system and can yield a biphasic effect on sleep such that THC, at lower doses, can reduce sleep onset latency and has been associated with greater ease of falling asleep, increased slow-wave sleep and increased total sleep time. CBD, the second most abundant cannabinoid found in cannabis, has been shown to have a dual effect on sleep latency. At lower doses, CBD can have a stimulating effect; however, at higher doses, it can have more of a sedating effect. It can increase total sleep time and decrease the frequency of arousals during the night.

The Safety Profile of Medical Cannabis

1. A Descriptive Analysis of Adverse Event Reports from the Quebec Cannabis Registry: Canadian patients authorized to use medical cannabis products report sustained improvements in their health-related quality of life, according to longitudinal data published in the journal Cannabis and Cannabinoid Research. A team of investigators affiliated with McGill University in Montreal assessed the safety and efficacy of medical cannabis products in a cohort of 2,991 patients. Subjects in the study consumed cannabis flower, extracts, or other related products for one year. Consistent with other studies, researchers reported: “All patient-reported outcomes showed a statistically significant improvement at 3 months, which was maintained or further improved (for pain interference, tiredness, and well-being) over the remainder of the 12-month follow-up. Results also revealed clinically significant improvements in pain interference and tiredness, anxiety, and well-being from baseline.” A total of 2991 patients were enrolled (mean age 50.9 years, 50.2% females). During follow-up, only 3.6% experienced moderate or severe adverse effects which included things like nausea, headaches, dizziness, and vomitting. Notable differences in adverse effect profiles between modes of administration and cannabinoid content ratios were noticed and should be noted by physicians.

2. A Semi-Naturalistic, Open-Label Trial Examining the Effect of Prescribed Medical Cannabis on Neurocognitive Performance: A recent study in the journal CNS Drugs found that medical marijuana patients who use the drug as prescribed do not experience meaningful negative cognitive effects after doing so. The researchers tested 40 patients by giving them a spectrum of cannabis products, including oils and flower, and then performing a battery of tests to measure cognitive performance. The authors found “no evidence for impaired cognitive function,” concluding, “these findings suggest that prescribed medical cannabis may have minimal acute impact on cognitive function among patients with chronic health conditions, although larger and controlled trials are needed.” The study’s lead author — Dr. Thomas Arkell of the Swinburne University of Technology’s Centre for Human Psychopharmacology — explained that “we already know that non-medical cannabis can impact memory and attention. However, our findings show that patients prescribed medical cannabis by a doctor don’t experience the same effects.”

3. Baby Boomers Rushing to Cannabis as a Way to Improve Memory Function and Mood: The researchers observed that while elevated levels of THC can yield adverse impacts on the developing adolescent brain, a contrary outcome emerges in the context of older brains. Notably, senior individuals who engage with cannabis exhibited notably enhanced neural communication between the cerebellum and hippocampus in comparison to their non-using counterparts. An unaffiliated researcher, Gary Wenk, Ph.D., said, “Utilizing low-dose, daily cannabis consumption beyond 55 may effectively counteract the deteriorative consequences stemming from persistent brain inflammation.”

Note: We do not claim that medical cannabis can cure any conditions but are just highlighting research that has been done on the topic of medical cannabis and various health conditions. The majority of these studies relate to the potential of medical cannabis in providing symptom relief and improving quality of life.

To learn more or speak with a medical cannabis specialist, book your free appointment today.

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