Endocannabinoid system modulation in acute, chronic, and neuropathic pain: reviewing experimental models, clinical evidence, and nanotechnology delivery

“Chronic pain is highly prevalent and inadequately managed by current therapeutic strategies, which present significant limitations such as the development of tolerance, dependence, and cognitive impairment. Therefore, searching for new pain management strategies is an ultimate goal.

The endocannabinoid system (ECS), is a broad crucial regulatory network in central nervous system’s development and in modulating various physiological and cognitive functions. It comprises endogenous cannabinoids, cannabinoid receptors, and the enzymes governing cannabinoid production and breakdown.

Recently, cannabinoids, particularly medical cannabis, have garnered renewed interest for their possibilities in treating different medical conditions, including chronic pain.

Although the risk of lethal overdose is negligible, the prevalence of non-serious adverse effects is significant and requires careful clinical consideration. Currently, there is a paucity of sufficient efficacy and long-term safety data to fully support the systematic use of medical cannabis for chronic non-malignant pain conditions.

Further research is crucial to unlock the future potential of these approaches and to delineate essential directions for exploring the ECS and its role in pain management. Advances in nanotechnology have enabled novel delivery platforms that address key limitations of cannabinoid-based therapies.

Nanocarriers, including lipid and polymeric nanoparticles, nanoemulsions, and self-emulsifying systems, can improve cannabinoid solubility, stability, bioavailability, and targeted delivery. Through controlled release and site-specific targeting, these systems hold promise for enhancing the analgesic efficacy and safety of cannabinoid therapeutics.”

https://pubmed.ncbi.nlm.nih.gov/42154330

https://link.springer.com/article/10.1007/s11011-026-01862-4

Effect of cannabidiol, cannabinol and tetrahydrocannabivarin in managing inflammatory pain

“Current medications used to treat the inflammatory pain either have limited effectiveness or may be associated with serious side effects. Non-psychoactive phytocannabinoids may have a better safety profile and could be used as an alternative approach to treat this condition.

The aim of this study was to test the potential of three phytocannabinoids, cannabinol (CBN), tetrahydrocannabivarin (THCV) and cannabidiol (CBD), in treating inflammatory pain.

The inflammatory pain was triggered in male rats by a single intra-articular knee injection of the complete Freund’s adjuvant (CFA). One week later, rats were given four daily administrations of ibuprofen, CBN, THCV or CBD. Our data demonstrated that CFA injection triggered an inflammatory response expressed as damage of the synovial tissue, reduced locomotor activity, increased mechanical and, to a lesser extent, thermal pain sensitivity, and loss of body weight.

All phytocannabinoids reduced mechanical hyperalgesia and had no or a minor effect on locomotor activity.

Treatment with CBN also lowered thermal hypersensitivity. Treatment with CBN and THCV recovered the body weight of CFA-injected rats. However, administration of CBD reduced body weight and elevated blood monocyte and granulocyte levels above those of the CFA-injected control animal group.

We conclude that CBN and THCV may have potential in managing inflammatory pain.”

https://pubmed.ncbi.nlm.nih.gov/42151379

https://www.nature.com/articles/s41598-026-51275-7

Electrophysiological modulation of pain‑related sodium channels by cannabinoids: a systematic review

“Voltage-gated sodium channels regulate dorsal root ganglion excitability and are critical for nociceptive transmission. Cannabidiol (CBD) and related phytocannabinoids have been proposed to modulate these channels, offering potential non-opioid analgesic strategies. This systematic review evaluated their in vitro effects on pain-related sodium channels, focusing on electrophysiological and biophysical mechanisms.

Following PRISMA guidelines, Embase®, LILACS®, PubMed®/MEDLINE®, and Scopus® were searched using the SPIDER strategy. Eligible studies evaluated CBD or its derivatives on voltage-gated sodium channels Nav1.3, Nav1.6, Nav1.7, Nav1.8, and Nav1.9 through electrophysiological assays. Data extraction and analysis were conducted independently by two reviewers, with inter-rater agreement assessed by Cohen’s kappa. Seven studies met the inclusion criteria.

CBD consistently inhibited sodium currents with IC₅₀ values in the low micromolar range (2–3.3 µM), reduced action potential firing, induced hyperpolarizing shifts in steady-state inactivation, and delayed recovery from inactivation. Other phytocannabinoids, such as cannabigerol, cannabinol, cannabigerolic acid, and cannabidivarinic acid, also inhibited sodium channels, though with variable potency and distinct effects on channel gating.

Cannabinoids, particularly CBD, act as non-selective inhibitors of voltage-gated sodium channels implicated in pain signaling. Their ability to stabilize inactivated channel states and reduce neuronal excitability supports their therapeutic potential in neuropathic pain. These findings highlight the relevance of phytocannabinoids as promising candidates for the development of non-opioid analgesics.”

https://pubmed.ncbi.nlm.nih.gov/41987259

https://link.springer.com/article/10.1186/s42238-026-00436-6





Therapeutic relevance of an EU-GMP certified Cannabis sativa L. strain in a dual in vivo model of cognitive impairment and chronic neuropathic pain

Background: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline and frequently co-occurs with chronic pain. Worldwide, over 55 million people are affected by AD, with nearly half experiencing persistent pain. Chronic pain has been linked to accelerated memory deterioration and an increased risk of dementia, but the interplay between these conditions remains poorly understood. Existing therapies for AD and chronic pain are limited in efficacy, highlighting the need for interventions targeting multiple pathological pathways. The endocannabinoid system, which is altered in both AD and chronic pain, represents a potential therapeutic target, though its role in AD patients with comorbid pain remains unexplored.

Methods: The study evaluated the effects of an EU-GMP certified Cannabis sativa L. strain (5 mg/kg, Cannabixir® Medium Flos) on neurobiological alterations in a rat model designed to explore mechanistic interactions between scopolamine-induced transient cognitive impairment and chronic neuropathic pain induced by unilateral sciatic nerve ligation. Treatment outcomes were assessed through nociceptive tests, clinical monitoring and tissue analyses to examine cognitive and pain-related effects.

Results: Cannabixir® Medium Flos induced robust, time-dependent analgesia in thermal nociceptive tests, with the combination of the Cannabis sativa L. strain, donepezil and tramadol producing significantly longer response latencies than tramadol alone. Mechanical sensitivity was minimally affected across treatments. Immunohistochemical analyses revealed that Cannabixir® Medium Flos, either alone or in combination with donepezil or tramadol, produced the most pronounced neuroprotective effects, reducing astrocytic (GFAP) and microglial (Iba1) activation, lowering Caspase-3 and IL-6 expression, and preserving both hippocampal neuronal integrity as well as peripheral nerve structure.

Conclusion: These findings indicate that Cannabixir® Medium Flos, particularly when combined with donepezil and tramadol, provides superior analgesic and neuroprotective effects compared to tramadol alone. Its multi-target action – alleviating thermal nociception, reducing neuroinflammation, limiting apoptosis and preserving neuronal and peripheral nerve integrity-supports its potential as an adjunct therapy in managing dementia with comorbid chronic neuropathic pain. Future studies should explore the molecular mechanisms underlying these effects and assess long-term safety and efficacy across diverse models of neurodegeneration and chronic pain.”

https://pubmed.ncbi.nlm.nih.gov/41800101

https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2026.1761426/full

Medical Cannabis for the Treatment of Peripheral Neuropathy due to Diabetes: A Systematic Review

Introduction: This systematic review evaluated randomized controlled trials (RCTs) conducted specifically in participants with diabetes and painful peripheral neuropathy to assess the effectiveness and safety of medical cannabis, isolated cannabinoids, or nationally approved cannabis-based medicines as adjuvant treatment, compared with placebo or baseline.

Materials and methods: Controlled clinical studies and RCTs in adults with diabetic peripheral neuropathy were eligible. Animal and in vitro studies were excluded. We searched PubMed, Google Scholar, Cochrane Library, and Scopus and screened 15,377 records; 35 full-text articles were assessed for eligibility, and 4 RCTs were included in the qualitative synthesis.

Results: Three of four studies reported statistically significant reductions in neuropathic pain with cannabinoid-based interventions compared with placebo, whereas one trial did not demonstrate superiority. In two trials using vaporized or sublingual Δ9-tetrahydrocannabinol (THC), doses in the range of approximately 16-18 mg were associated with clinically meaningful pain relief in participants. Adverse effects, including dizziness and cognitive symptoms, were common but generally mild-to-moderate, and discontinuations due to adverse effects varied across studies.

Discussion/conclusion: Evidence from four small, heterogeneous RCTs suggests that cannabinoid-based therapies may reduce pain in some patients with diabetic peripheral neuropathy; however, the limited number of studies, variability in formulations and comparators, and risk of bias preclude firm conclusions regarding efficacy. Observed THC doses around 16-18 mg/day delivered via vaporized or sublingual routes should be viewed as preliminary, hypothesis-generating ranges rather than definitive recommendations. Larger, contemporary RCTs with rigorous risk-of-bias control, standardized outcomes, and detailed safety reporting are needed.”

https://pubmed.ncbi.nlm.nih.gov/41714301

“three of four identified studies demonstrated statistically significant reductions in pain compared with placebo or baseline, suggesting that cannabinoid-based interventions may offer analgesic benefit for some patients with diabetic peripheral neuropathy.”

https://journals.sagepub.com/doi/10.1177/25785125261425444

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

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

Neuropathic Pain and Related Depression in Mice: The Effect of a Terpene and a Minor Cannabinoid in Combination

Background/Objectives: Neuropathic pain is one of the most severe types of chronic pain. Although it is difficult to manage, it often co-occurs with depression. Yet, no medication addresses the neuropathic pain and depression comorbidity. Therefore, developing integrated treatment strategies that address both pain and depression is a major public health priority and an unmet need affecting millions. 

Methods: In this study, we investigated the effect of combining a terpene, Beta-Caryophyllene (BCP), and cannabidiol (CBD) on neuropathic pain and associated depression. We employed a chronic constriction injury (CCI) neuropathic pain model and a series of behavioral tests to evaluate how oral administration of this combination influences neuropathic pain and depression-like behaviors in mice. We employed immunohistochemistry and proteomics approaches to explore the mechanism. 

Results: The analgesic effect of combining CBD and BCP is synergistic in neuropathic pain and also shows an antidepressant effect. Additionally, we found that this combination decreases neuroinflammation associated with CCI and affects specific genes involved in the inflammation. 

Conclusions: This work provides preclinical scientific evidence supporting the potential usefulness of this combination for neuropathic pain and associated depression.”

https://pubmed.ncbi.nlm.nih.gov/41463111

“Cannabis plants contain various non-psychoactive compounds, including Caryophyllene (BCP). BCP is a natural bicyclic sesquiterpene that acts as a natural ligand for the cannabinoid type 2 receptor (CB2) and is an FDA-approved food additive. It has several benefits, such as pain relief, antidepressant effects, and anti-inflammatory properties.

Given this background, the main goal of this study is to test the hypothesis that combining CBD and BCP is effective for neuropathic pain while also demonstrating antidepressant effects.”

“In conclusion, the proposed project introduces the concept that the combination of CBD and BCP can effectively relieve neuropathic pain while also addressing depression. This knowledge will advance the field by providing preclinical scientific evidence supporting the potential usefulness of this combination for neuropathic pain and associated depression.”

https://www.mdpi.com/2227-9059/13/12/3103


Modulatory Effects of “Minor” Cannabinoids in an in vitro Model of Neuronal Hypersensitivity

Aim: Effective treatment for neuropathic pain remains an unmet clinical need. The therapeutic benefits of the Cannabis plant are well known, especially for pain relief. Here, we have assessed ten “minor” cannabinoids for their analgesic effects in an established model of neuronal hypersensitivity, a key mechanism which underlies neuropathic pain.

Methods: Adult rat DRG neurons were cultured in medium containing 100 ng/mL nerve growth factor (NGF) and 50 ng/mL glial cell-line derived neurotrophic factor (GDNF) for 48 hours to sensitize the neurons. Ca2+ imaging was used to measure the responses to pain stimulation using capsaicin, and to determine the modulatory effects of the cannabinoids, in individual neurons.

Results: Control neurons (nociceptors) showed robust responses of Ca2+ influx to capsaicin application, while neurons treated with ten minor cannabinoids tetrahydrocannabiorcol (THCC), cannabitriol (CBT), cannabidivarin (CBDV), cannabinol (CBN), cannabichromene (CBC), cannabichromevarin (CBCV), cannabicitran (CBCT), cannabigerol monomethyl ether (CBGM), tetrahydrocannabutol (THCB) or tetrahydrocannabiphorol (THCP), at concentrations of 0.001-100 μM, showed differential dose-related effects on the responses to capsaicin. Ca2+ influx in response to capsaicin application was completely inhibited for each compound in 35-78% capsaicin-sensitive neurons, while other neurons showed reduced responses. The opioid receptor agonist morphine and α2δ1- Ca2+ channel inhibitor gabapentin were also tested for comparison and showed similar results. All the cannabinoids tested here inhibited calcium influx in response to capsaicin, and two, namely, CBN and THCC elicited calcium influx at higher doses. Inhibition of Ca2+ influx due to cannabichromene (CBC) was reversed by the potassium channel inhibitor Tertiapin Q.

Conclusion: All the cannabinoids tested here inhibited TRPV1 signalling. CBC targeted K+ channels to block TRPV1 mediated Ca2+ influx, demonstrating potential analgesic effects in vitro.”

https://pubmed.ncbi.nlm.nih.gov/41322279

“The therapeutic benefits of the Cannabis plant are well known, especially for pain relief.”

“In conclusion, our results show that the minor cannabinoids potently inhibit TRPV1 signaling in sensitized DRG neurons, and for CBC by blocking Ca2+ influx via K+ channel activation. This conclusion is based on the reversal of CBC-mediated inhibition in the presence of the K+ channel inhibitor Tertiapin Q. Further studies are necessary to confirm the mechanism, pathways and targets involved in the observed inhibitory effects of the other minor cannabinoids. This will facilitate the identification of cannabinoid combinations likely to have the maximum effect in providing analgesia for inhibiting neuronal sensitization that underlies chronic pain.”

https://www.dovepress.com/modulatory-effects-of-minor-cannabinoids-in-an-in-vitro-model-of-neuro-peer-reviewed-fulltext-article-JPR

Use of Cannabidiol and Cannabigerol in the Treatment of Trigeminal Neuralgia and Postherpetic Pain

“The use of cannabidiol (CBD) as an adjuvant in the treatment of trigeminal neuralgia (TN) and postherpetic neuropathy has shown beneficial effects in patients refractory to conventional treatments.

This case study describes a 57-year-old patient diagnosed with TN in 2019, initially treated with low-power laser therapy and oxcarbazepine. In 2021, she developed vesicular-bullous lesions on the right side of the supraorbital region, accompanied by severe pain confirmed by positive serology for shingles. Following the diagnosis of postherpetic neuropathy, the drug dose was adjusted and combined with laser therapy. However, the pain remained significant and reduced quality of life.

In 2023, treatment was started with CannaMeds CBD Full Spectrum – 3000 mg/30 ml + CannaMeds CBG Isolate 1500 mg/30 ml. After 15 days, the patient appeared pain-free, allowing the laser to be discontinued and the drug dose to be reduced.

CBD is a treatment option for patients who do not respond to conventional treatments.”

https://pubmed.ncbi.nlm.nih.gov/41281696

“It is difficult to find an effective treatment for these conditions, because over time patients no longer respond to treatment. Therefore, the use of CBD and cannabigerol could be an adjuvant treatment option for patients who do not respond to conventional treatment for neuropathic pain.”

https://journals.lww.com/cocd/fulltext/2025/07000/use_of_cannabidiol_and_cannabigerol_in_the.10.aspx