“Corneal injury can result in dysfunction of corneal nociceptive signaling and corneal sensitization.
Activation of the endocannabinoid system has been reported to be analgesic and anti-inflammatory.
The purpose of this research was to investigate the antinociceptive and anti-inflammatory effects of cannabinoids with reported actions at cannabinoid 1 (CB1R) and cannabinoid 2 (CB2R) receptors and/or noncannabinoid receptors in an experimental model of corneal hyperalgesia.
Topical cannabinoids reduce corneal hyperalgesia and inflammation.
The antinociceptive and anti-inflammatory effects of Δ8THC are mediated primarily via CB1R, whereas that of the cannabinoids CBD and HU-308, involve activation of 5-HT1A receptors and CB2Rs, respectively.
Cannabinoids could be a novel clinical therapy for corneal pain and inflammation resulting from ocular surface injury.”
“Cannabinoids have been used for their analgesic and euphoric effects for millennia, but recently the antipruritic effects of cannabis have been discovered.
Considering the similarities between pain and itch sensations, we hypothesized that cannabinoid receptors may play a role in the antipruritic effects of cannabinoids.
Our findings support prior researches indicating that cannabinoids exert antipruritic effects. Moreover, our results show that the antipruritic effects of cannabinoids are partially mediated by spinal CB1 receptors.”
“Some cannabinoids have been shown to suppress chronic pain by targeting glycine receptors (GlyRs).
Although cannabinoid potentiation of α3 GlyRs is thought to contribute to cannabinoid-induced analgesia, the role of cannabinoid potentiation of α1 GlyRs in cannabinoid suppression of chronic pain remains unclear.
Here we report that dehydroxylcannabidiol (DH-CBD), a nonpsychoactive cannabinoid, significantly suppresses chronic inflammatory pain caused by noxious heat stimulation.
These findings suggest that spinal α1 GlyR is a potential target for cannabinoid analgesia in chronic inflammatory pain.”
“Many cultures throughout history have used cannabis to treat a variety of painful ailments. Neuropathic pain is a complicated condition that is challenging to treat with our current medications.
Recent scientific discovery has elucidated the intricate role of the endocannabinoid system in the pathophysiology of neuropathic pain. As societal perceptions change, and legislation on medical cannabis relaxes, there is growing interest in the use of medical cannabis for neuropathic pain.
We examined current basic scientific research and data from recent randomized controlled trials (RCTs) evaluating medical cannabis for the treatment of neuropathic pain.
These studies involved patients with diverse etiologies of neuropathic pain and included medical cannabis with different THC concentrations and routes of administration. Multiple RCTs demonstrated efficacy of medical cannabis for treating neuropathic pain, with number needed to treat (NNT) values similar to current pharmacotherapies.
Although limited by small sample sizes and short duration of study, the evidence appears to support the safety and efficacy of short-term, low-dose cannabis vaporization and oral mucosal delivery for the treatment of neuropathic pain.
The results suggest medical cannabis may be as tolerable and effective as current neuropathic agents; however, more studies are needed to determine the long-term effects of medical cannabis use. Furthermore, continued research to optimize dosing, cannabinoidratios, and alternate routes of administration may help to refine the therapeutic role of medical cannabis for neuropathic pain.”
“Chronic pain is common in the United States and prescribed opioid analgesics use for noncancer pain has increased dramatically in the past two decades, possibly accounting for the current opioid addiction epidemic. Co-morbid drug use in those prescribed opioid analgesics is common, but there are few data on polysubstance use patterns.
We explored patterns of use of cigarette, alcohol, and illicit drugs in HIV-infected people with chronic pain who were prescribed opioid analgesics.
Almost half of the sample of people with HIV and chronic pain reported current prescribed opioid analgesic use (N = 372, 47.1%). Illicit drug use was common (N = 505, 63.9%), and cannabis was the most commonly used illicit substance (N = 311, 39.4%).
In multivariate analyses, only cannabis use was significantly associated with lower odds of prescribed opioid analgesic use (adjusted odds ratio = 0.57; 95% confidence interval: 0.38-0.87).
Conclusions/Importance: Our data suggest that new medical cannabis legislation might reduce the need for opioid analgesics for pain management, which could help to address adverse events associated with opioid analgesic use.”
“Targeting the endocannabinoid system has emerged as an effective strategy for the treatment of inflammatory and neurological diseases.
Unlike the inhibition of the principal 2-arachidonyl glycerol (2-AG) hydrolytic enzyme monoacylglycerol lipase (MAGL), which leads to 2-AG overload and cannabinoid receptor desensitization, selective inhibition of the minor 2-AG hydrolytic enzyme alpha, beta-hydrolase domain 6 (ABHD6) can provide therapeutic benefits without producing cannabimimetic side effects. We have shown that inhibition of ABHD6 significantly reduces neuroinflammation and exerts neuroprotection in animal models of traumatic brain injury and multiple sclerosis. However, the role of ABHD6 inhibition on neuropathic pain has not been explored.
This study reveals a novel mechanism for the antinociceptive effect of the 2-AG catabolic enzyme ABHD6 inhibitor WWL70. Understanding the interaction between endocannabinoid and eicosanoid pathways might provide a new avenue for the treatment of inflammatory and neuropathic pain.”
“The endocannabinoid system (ECS) plays a diverse role in human physiology ranging from the regulation of mood and appetite to immune modulation and the response to pain.
Drug development that targets the cannabinoid receptors (CB1 and CB2) has been explored; however, success in the clinic has been limited by the psychoactive side effects associated with modulation of the neuronally expressed CB1 that are enriched in the CNS. CB2, however, are expressed in peripheral tissues, primarily in immune cells, and thus development of CB2-selective drugs holds the potential to modulate pain among other indications without eliciting anxiety and other undesirable side effects associated with CB1 activation.
As part of a collaborative effort among industry and academic laboratories, we performed a high-throughput screen designed to discover selective agonists or positive allosteric modulators (PAMs) of CB2. Although no CB2 PAMs were identified, 167 CB2 agonists were discovered here, and further characterization of four select compounds revealed two with high selectivity for CB2 versus CB1.
These results broaden drug discovery efforts aimed at the ECS and may lead to the development of novel therapies for immune modulation and pain management with improved side effect profiles.”
“Efficacious treatment for neuropsychiatric symptoms (NPS), pain and weight loss for dementia patients is desperately needed.
This review presents an up-to-date look at the literature investigating the use of cannabinoid for these symptoms in dementia.
We searched electronically for publications regarding cannabinoid use in dementia, with a focus on Alzheimer’s disease. Seven studies and one case report have been conducted to examine the use of cannabinoids for the treatment of NPS of dementia, and three of these trials reported on the effect of cannabinoids on weight. Five studies reported decreased agitation or improvements in sleep with cannabinoid use. One crossover trial found that cannabinoids positively impacted weight, whereas a chart review study found no impact on weight with cannabinoids, but an increase in food intake. There were no trials examining the use of cannabinoids for pain in dementia.
Findings from trials with small sample sizes and various clinical populations suggest that cannabinoid use may be well tolerated and effective for treatment of NPS such as agitation as well as weight and pain management in patients with dementia. Additional studies are necessary to further elucidate the relative risks and benefits of this treatment.”
“The Public Health Program at Stockton University partnered with the Compassionate Care Foundation to ascertain the impact of medical marijuana on patients in New Jersey.
Results provide insight into the diagnoses for which patients used medical marijuana.
Results indicate increased mood, general overall condition, and energy as the highest consequences; level of pain in the middle range; and most frequent usage as 3 to 4 times a day. Repeated measures done after visit 2 showed eight statistically significant differences for patients after using medical marijuana: an increase in general quality of life, mobility, and mood, with a decrease in inflammation, intraocular pressure, spasms, seizures, and pain.
Results after visit 3 indicated seven significant differences compared to visit 1: decreased seizures, intraocular pressure, spasms, nausea, and pain, along with increased energy and mobility. No differences were found by patient diagnosis or age, but sex-related differences occurred in inflammation, mood, and energy.
Results support positive therapeutic benefits of medical marijuana, and despite methodological limitations, our study contributes to the growing body of literature.”
“Pain is a significant clinical problem, and there is a need for effective pharmacotherapies with fewer adverse effects than currently available drugs (e.g., mu opioid receptor agonists).
Cannabinoid receptor agonists enhance the antinociceptive effects of mu opioid receptor agonists, but it remains unclear which drugs and in what proportion will yield the most effective and safest treatments.
The antinociceptive effects of the mu opioid receptor agonists etorphine and morphine alone and in combination with the cannabinoid receptor agonists Δ9-THC and CP55940 were studied in male Sprague-Dawley rats (n=16) using a warm water tail withdrawal procedure.
The ratio of opioid to cannabinoid (3:1, 1:1, and 1:3) varied for each mixture. Drugs administered alone or as pairwise mixtures of an opioid and a cannabinoid dose-dependently increased tail withdrawal latency. Mixtures with morphine produced supra-additive (CP55940) and additive (Δ9-THC) effects, whereas mixtures with etorphine and either cannabinoid were sub-additive. The interactions were not different among ratios for a particular mixture.
The nature of the interaction between opioids and cannabinoids with regard to antinociceptive effects varies with the particular drugs in the mixture, which can have implications for designing combination therapies for pain.”