Ewing sarcoma-related pain: potential role of medical cannabis monotherapy in symptom management – a case report

“Persistent, multimodal cancer pain remains a challenge, particularly in long-term survivors facing treatment-related complications. The management of high-dose opioid dependence concurrent with chronic, multi-drug resistant (MDR) periprosthetic infection presents a critical unmet need. This case reports the potential use and sustained efficacy of medical cannabis monotherapy, highlighting an unexpected temporal association with the resolution of inflammatory and infectious symptoms in a highly complex oncologic setting.

Case presentation

A 27-year-old male, a long-term survivor of high-risk Ewing Sarcoma of the proximal tibia, presented with intractable mixed pain (VAS 9–10) secondary to chronic, recurrent MDR periprosthetic osteomyelitis and multiple surgical revisions (2013–2024). Despite continuous use of high-dose opioids (up to 120 mg/day morphine equivalents), pain levels remained moderate-to-severe (VAS 6–7) and functional status was poor. The patient had previously found temporary relief with self-administered cannabis. In January 2025, after refusing limb amputation, supervised medical cannabis therapy (Bedrocan®, 22% THC, 1% CBD, 1 g/day) was initiated. Pain levels gradually stabilized at VAS 2–3, coinciding with complete opioid discontinuation within four weeks. Over nine months of follow-up, the patient maintained full autonomy and an active lifestyle. Notably, sustained cannabis monotherapy was associated with the complete closure of the chronic draining fistula and a reduction in systemic inflammatory markers (CRP from 9.6 to 2.3 mg/dL). No significant adverse effects were reported.

Conclusions

This case suggests that THC-rich medical cannabis may represent a feasible strategy for achieving opioid-free analgesia in selected patients with refractory oncologic pain. While causality cannot be established from a single observation, the correlation between cannabis initiation and the resolution of severe chronic inflammatory and infectious symptoms is intriguing and suggests a potential pleiotropic role extending beyond traditional pain management. While these findings align with emerging evidence highlighting the potent immunomodulatory and anti-inflammatory properties of cannabinoids, they contrast with some recent neutral meta-analyses in broader populations, an this would justify warrant urgent controlled investigation into the potential mechanisms of cannabinoids in complex inflammatory pain states and their role as a possible adjunct in managing long-term oncological complications.”

https://pubmed.ncbi.nlm.nih.gov/41572388

https://link.springer.com/article/10.1186/s42238-026-00388-x

Perceived impact of medicinal cannabis on pelvic pain and endometriosis related symptoms in Aotearoa New Zealand: an observational cohort study

“Endometriosis, characterised by the growth of endometrial-like tissue outside the uterus, often causes severe pelvic pain, dysmenorrhea, and fatigue. Current medical treatments frequently provide incomplete symptom control and/or significant side effects. Many individuals with endometriosis report symptom improvements with cannabis use, but high-quality evidence remains limited.

Methods

A prospective, mixed-methods cohort study was conducted. Participants aged 18–50 years with surgically or clinically diagnosed endometriosis self-engaged with a specialist consultant and were prescribed medicinal cannabis (cannabidiol [CBD] oil alone or in combination with dried cannabis flower). Weekly pain scores, and health-related quality of life (measured by the Endometriosis Health Profile-30 [EHP-30]) were assessed via surveys and standardised questionnaires over three months. Completion interviews were conducted to explore participants’ experiences with medicinal cannabis in greater depth.

Results

Participants reported limited adverse events during the study period. Pelvic pain scores decreased over 12 weeks: ‘overall’ pain reduced from 5.46 ± 1.55 (95% CI 0.57) to 3.77 ± 2.25 (95% CI 0.83), and ‘worst’ pain decreased from 7.62 ± 1.51 (95% CI 0.56) to 5.38 ± 2.69 (95% CI 1.00). The mean total EHP-30 score significantly decreased from 68.77 ± 15.17 (95% CI 5.61) to 37.40 ± 16.66 (95% CI 6.17). Qualitative analysis identified four major themes: motivations for seeking medicinal cannabis, experiences of use, barriers to use, and stigma.

Conclusions

Medicinal cannabis use was associated with reduction in pain measures and improvements in quality of life among some individuals with endometriosis during this study. Qualitative findings highlighted both perceived benefits and ongoing challenges related to access, dosage and social stigma. These results support the need for larger controlled studies to further evaluate the safety, efficacy, and long-term outcomes of medicinal cannabis as an adjunctive therapy for endometriosis-related pain.”

https://pubmed.ncbi.nlm.nih.gov/41566248

https://link.springer.com/article/10.1186/s12906-025-05189-y

The psychoactive cannabinoid THC inhibits peripheral nociceptors by targeting NaV1.7 and NaV1.8 nociceptive sodium channels

“Δ⁹-Tetrahydrocannabinol (THC), the primary psychoactive compound in cannabis, is widely recognized for its central effects mediated by cannabinoid receptors. Here, we uncover a distinct peripheral mechanism by which THC inhibits the excitability of nociceptive neurons.

We show that THC directly targets the nociceptive voltage-gated sodium channels NaV1.7 and NaV1.8 through the conserved local anesthetic binding site. This interaction reduces sodium currents and suppresses action potential generation in peripheral sensory neurons.

Our findings demonstrate that, beyond its central psychoactivity, THC exerts direct peripheral nociceptor inhibition via modulation of NaV1.7 and NaV1.8, offering new insight into cannabinoid-based analgesia independent of cannabinoid receptor signaling.”

https://pubmed.ncbi.nlm.nih.gov/41565997

“Cannabis has been used for centuries for its analgesic properties, and its clinical relevance in pain management continues to grow.”

 “These findings reveal a previously unrecognized mechanism for THC-mediated peripheral analgesia and establish a non-canonical molecular pathway through which the psychoactive cannabinoid can inhibit nociceptor excitability and thereby pain.”

https://www.nature.com/articles/s41386-026-02355-9

The Evidence for Medical Cannabis in Chronic Musculoskeletal Pain Management

“Chronic musculoskeletal pain (CMP) is a pervasive condition that can impair daily functioning and quality of life. Traditional pharmaceutical therapies, including non-steroidal anti-inflammatory drugs, gabapentinoids, and opioids, often yield suboptimal results and carry notable risks, such as adverse side effects and dependence.

Increasing interest has turned toward medical cannabis, particularly combined formulations of cannabidiol (CBD) and tetrahydrocannabinol (THC), as a potential alternative or complement to current pain management strategies.

Evidence suggests that cannabinoids interact with the endocannabinoid system to modulate nociception and inflammation, offering meaningful pain relief and possibly reducing opioid requirements.

However, heterogeneity in study designs, product formulations, and regulatory frameworks presents challenges in drawing definitive conclusions. Additionally, while most adverse effects, such as fatigue, dizziness, and mild cognitive changes, are generally reported as tolerable, concerns remain about long-term safety and standardization of dosing.

Taken together, the existing literature points to a promising role for medical cannabis in CMP management, underscoring the need for further high-quality research to establish best practices, clarify patient selection, and guide clinicians in safe and effective cannabinoid therapy.”

“This scoping review highlights the potential role of medical cannabis in managing musculoskeletal pain. Evidence suggests it may reduce pain, enhance well-being, and improve quality of life, particularly as an alternative or adjunct to opioids. Adverse effects are typically mild, supporting its use as a safer long-term option. However, data on long-term efficacy, especially for CBD, remain limited.

Given the risks of opioid dependence, cannabis offers a promising therapeutic alternative.”

https://surgicoll.scholasticahq.com/article/138573-the-evidence-for-medical-cannabis-in-chronic-musculoskeletal-pain-management

Cannabidiol reduces oxycodone self-administration while preserving its analgesic efficacy in a rat model of neuropathic pain

“Prescription opioid misuse is a significant public health concern among individuals with chronic pain. Treating severe pain often requires high doses of opioids, increasing the risk of developing an opioid use disorder.

Cannabidiol (CBD) is a non-intoxicating component of cannabis that has shown therapeutic potential without abuse liability.

This study investigated the effects of CBD on oxycodone self-administration and hyperalgesia in an animal model of chronic neuropathic pain.

Adult male rats were trained to self-administer intravenous oxycodone (0.06 mg/kg/infusion). Subsequently, they underwent chronic constriction injury (CCI) of the sciatic nerve or received sham surgery. Paw withdrawal latency was measured using the Hargreaves test as an indicator of thermal pain sensitivity. CBD (0, 1, 3, and 10 mg/kg, IP) was administered before the self-administration sessions, and pain testing was conducted afterward. The rats acquired oxycodone self-administration, as indicated by more active than inactive lever presses. CCI surgery decreased the paw withdrawal latency, confirming the induction of neuropathic pain. CCI alone did not affect oxycodone self-administration, suggesting that neuropathic pain does not substantially influence opioid intake at the dose tested.

Treatment with CBD reduced oxycodone self-administration in both the sham and CCI rats. Oxycodone self-administration in the CCI rats reversed the CCI-induced decrease in paw withdrawal latency. However, CBD did not affect the antinociceptive effect of oxycodone in CCI rats.

Taken together, these findings demonstrate that CBD reduces oxycodone self-administration without affecting the antinociceptive effects of oxycodone in neuropathic pain.

This study supports the potential of CBD to reduce opioid use and misuse, regardless of pain status.”

https://pubmed.ncbi.nlm.nih.gov/41521216

https://www.nature.com/articles/s41598-025-31828-y

Intravesical Cannabidiol for Inflammation and Pain in Interstitial Cystitis/Bladder Pain Syndrome via TLR4/NF-κB and TRPV1 Modulation

Purpose: This study explored the anti-inflammatory and analgesic mechanisms of intravesical cannabidiol (CBD) in cyclophosphamide (CYP)-induced interstitial cystitis/bladder pain syndrome (IC/BPS) rats.

Materials and methods: Female Sprague-Dawley rats were divided into four groups of control, IC/BPS, IC/BPS+10 mg/kg CBD, and IC/BPS+100 mg/kg CBD (n=5/group). IC/BPS was induced by CYP injections, followed by intravesical CBD administration. Pain sensitivity and bladder function were assessed via Von Frey tests and cystometrograms. Histological, Western blot, and immunofluorescence analyses were performed on bladder tissues. SV-HUC1 cells were analyzed using western blot and scratch assays.

Results: CBD improved bladder function, reducing instability, prolonging intercontractile intervals, and enhancing detrusor contraction pressure. The CBD 100 mg/kg group showed greater pain relief in Von Frey tests compared with other groups. Histology revealed reduced inflammation, mast cell infiltration, and fibrosis in bladder tissues. CBD decreased TNF-α, COX2, IL-6, and TRPV1 levels and inhibited the TLR4/MyD88/pNF-κB pathway. In SV-HUC1 cells, CBD suppressed epithelial injury and downregulated TRPV1, TLR4, MyD88, p-NF-κB, and Bax/Bcl-xL, demonstrating anti-inflammatory and anti-apoptotic effects.

Conclusions: Intravesical CBD alleviates inflammation by inhibiting the TLR4/MyD88/pNF-κB pathway, reduces neuropathic pain via TRPV1 channels, and improves cell apoptosis and migration in CYP-induced IC/BPS model animals.”

https://pubmed.ncbi.nlm.nih.gov/41508393

“Cannabidiol (CBD) is a non-psychoactive cannabinoid with a variety of biological activities and a wide range of benefits such as antioxidant, anti-inflammatory, and immunomodulatory effects. Research has demonstrated the therapeutic significance of CBD in neurological disorders, cardiomyopathy, diabetes, and other diseases.”

“In the present study, we investigated the potential therapeutic effects of CBD in IC/BPS. We conducted intravesical instillation of CBD in a rat model of IC/BPS and evaluated the effects on inflammation and bladder function and pain. We further analyzed its mechanism of action. Our study provides evidence of the potential effectiveness of CBD in the treatment of IC/BPS.”

https://wjmh.org/DOIx.php?id=10.5534/wjmh.250152

Cross-sectional comparison of cannabis use in adults with neuropathic versus non-neuropathic pain

Introduction: Cannabis has been decriminalized by many states and shows promise in treating both neuropathic and non-neuropathic pain through its interaction with the endocannabinoid system and anti-inflammatory effects. This study examines differences in cannabis use for adults whose most bothersome chronic pain condition is neuropathic vs. non-neuropathic.

Materials and methods: Survey data were collected from adults receiving care at a pain clinic. Participants completed demographic questions and standardized self-report measures (PROMIS Pain Intensity/Interference and the ID-Pain tool). Participants’ most bothersome pain condition(s) were categorized as neuropathic or non-neuropathic pain based on ID-Pain scores. Linear regression models assessed differences in frequency and duration of cannabis product use between groups, adjusting for age and sex.

Results: A total of 113 individuals were recruited; following exclusions and missing data, 104 participants (61.5% female) were included in the final analysis. Of these, 36.5% reported neuropathic pain as their most bothersome, and 63.5% reported non-neuropathic pain. Those with neuropathic pain reported significantly more days per month of Tetrahydrocannabinol/Cannabidiol (THC/CBD) combination (b = 5.96, p = 0.02), Cannabidiol-only (CBD-only) (b = 8.82, p = 0.03), and Tetrahydrocannabinol-only (THC-only) products (b = 7.04, p = 0.02). They also used THC-only (b = 0.97, p < 0.05) and THC/CBD (b = 1.09, p < 0.01) products more frequently per day. Neuropathic pain was positively associated with pain intensity (b = 4.10, p < 0.001) and interference (b = 4.95, p < 0.001).

Discussion: Adults whose most bothersome pain condition(s) were neuropathic used cannabis, especially THC and THC/CBD combination products, more frequently than those whose most bothersome pain was non-neuropathic. Participants with neuropathic pain also reported higher levels of pain intensity and interference. Further longitudinal research is needed to confirm whether increased use of THC-rich cannabis provides symptom relief for adults with neuropathic pain.”

https://pubmed.ncbi.nlm.nih.gov/41487383

“Cannabis interacts with the endocannabinoid system, making it a potential treatment for neuropathic pain.”

“Because previous studies found THC products to be more effective in managing neuropathic pain by interacting with the endocannabinoid system, it is possible that our participants also experienced benefit; this could explain their higher use of THC containing products.

https://www.frontiersin.org/journals/pain-research/articles/10.3389/fpain.2025.1677391/full

Effect of patient marijuana use on perioperative opioid requirements

“The effect of chronic marijuana use on patients is unknown, including in the surgical setting. Marijuana produces many effects on the body, which should be considered when providing medical care.

Chronic marijuana use may affect surgical opioid requirements. To explore this possibility, an observational study was completed by conducting a retrospective chart review of patients who underwent surgery with general anesthesia.

Patients were identified in the electronic medical record via self-reporting as marijuana users (users) or nonmarijuana users (nonusers). Users and nonusers were case-matched based on age, gender, weight, and procedure. After case matching, 570 patients’ charts were analyzed, and intraoperative opioid, intraoperative propofol, and post-anesthesia care unit opioid requirements were compared.

Marijuana users required less intraoperative opioids (mean [standard deviation (SD)] 27.2 [20.5] morphine milligram equivalents [MMEs]) compared to those who were marijuana nonusers (31.3 [22.1] MME).

These results show a statistically significant difference in the intraoperative opioid requirement between case-matched users and nonusers (p = 0.02), with p = 0.013 after statistical adjustment for racial differences between the marijuana user and nonuser cohorts. Users and nonusers required similar amounts of intraoperative propofol (242.2 [220.2] and 257.8 [250.9], respectively) and post-operative opioids (7.3 [6.0] and 8.0 [9.0], respectively). The differences in intraoperative propofol and post-operative opioid requirements were not different statistically with p-values of 0.43 and 0.31, respectively.

Based on this study population, marijuana users required less intraoperative opioids when compared to case-matched marijuana nonusers, with no difference in intraoperative propofol or post-operative opioid requirements.

Perspective: Typical preoperative screening includes queries about patient substance use including marijuana, but details such as frequency and length of use are infrequently asked. The addition of these details to the assessment may provide improved understanding of a patient’s surgical opioid requirements.”

https://pubmed.ncbi.nlm.nih.gov/41123263

https://wmpllc.org/ojs/index.php/jom/article/view/3918

Medical Cannabis and Opioid Receipt Among Adults With Chronic Pain

Question  Is participation in the New York State (NYS) medical cannabis program associated with reduced prescription opioid receipt among adults with chronic pain?

Findings  In this cohort study of 204 adults with chronic pain, participation in the NYS medical cannabis program, defined as monthly dispensation of medical cannabis reported by the dispensary pharmacist, was associated with significantly reduced prescription opioid receipt.

Meaning  These findings suggest that participation in a pharmacist-directed medical cannabis program may help reduce prescription opioid receipt among adults with chronic pain.

Abstract

Importance  Medical cannabis is increasingly considered a substitute for prescription opioid medications for chronic pain, driven by the urgent need for opioid alternatives to combat the ongoing epidemic.

Objective  To determine the association between participation in the New York State (NYS) medical cannabis program and prescription opioid receipt among adults with chronic pain.

Design, Setting, and Participants  This cohort study used data from the NYS Prescription Monitoring Program (PMP) from September 2018 through July 2023. Adults prescribed opioids for chronic pain who were newly certified for medical cannabis use in NYS were recruited from a large academic medical center and nearby medical cannabis dispensaries in the Bronx, New York. Monthly dispensation of medical cannabis to study participants was monitored for 18 months. Data analyses were performed from February 3, 2025, to July 15, 2025.

Exposure  Portion of days covered each month by pharmacist report of dispensed medical cannabis.

Main Outcomes and Measures  Prescription opioid receipt, defined as NYS PMP-reported prescription monthly opioid dispensation (mean daily dose in morphine milliequivalents [MME]), was assessed with marginal structural models adjusted for time-invariant and time-varying confounders, including self-reported unregulated cannabis use. Nonprescribed opioid use was also assessed during the study period.

Results  Among 204 participants, the mean (SD) age at baseline was 56.8 (12.8) years, and 113 (55.4%) were female. At baseline, participants’ mean (SD) pain severity score was 6.6 (1.8) out of 10, and mean (SD) pain interference score was 6.8 (1.9) out of 10. Baseline mean (SD) daily MME was 73.3 (133.0). During the 18-month follow-up period, participants’ mean (SD) daily MME decreased to 57.4 (127.8). This reduction in mean daily MME was associated with the monthly portion of days covered with medical cannabis; compared with no medical cannabis dispensed, participants dispensed a 30-day supply of medical cannabis were exposed to 3.53 fewer MME per day (β = −3.53; 95% CI, −6.68 to −0.04; P = .03).

Conclusions and Relevance  In this cohort study, participation in NYS’s medical cannabis program was associated with reduced prescription opioid receipt during 18 months of prospective follow-up, accounting for unregulated cannabis use.”

https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2842414

Medical Cannabis Program Lowers Chronic Pain Opioid Prescriptions

“Access to medical cannabis through a state-regulated program was associated with significantly lower rates of opioid prescriptions among adults with chronic pain, according to findings recently published in JAMA Internal Medicine.

The study included 204 adults enrolled in the New York State medical cannabis program, which provided monthly access to medical cannabis through a dispensary pharmacist, and 142 ultimately obtained the treatment. The data spanned from September 2018 through July 2023. Researchers measured prescription opioid receipt via mean daily dose in morphine milliequivalents (MME) and compared it with how many days’ worth of cannabis individuals were dispensed each month based on pharmacists’ reports.

After 18 months, the mean daily MME decreased by 22%, from 73 to 57.

The authors noted that instead of measuring medical cannabis exposure via its legalization status, they directly analyzed pharmacy dispensation amounts, a more accurate indicator of uptake. Randomized clinical trials are needed to see whether medical cannabis reduces opioid use, they added.”

https://pubmed.ncbi.nlm.nih.gov/41481315

https://jamanetwork.com/journals/jama/fullarticle/2843608