Therapeutic potential of cannabis in pain medicine†

Posted on April 27, 2015 by David

BJA

“Cannabis has been of medicinal and social significance for millennia.

It is obtained from Cannabis sativa and the plant’s name reflects its ancient use—cannabis may represent a compound of Sanskrit and Hebrew words meaning ‘fragrant cane’, while sativa is Latin for cultivated.

Cannabis is also known as hemp.

Marijuana describes the dried cannabis flowers and leaves which are smoked, while hashish refers to blocks of cannabis resin which can be eaten.

Advances in cannabis research have paralleled developments in opioid pharmacology whereby a psychoactive plant extract has elucidated novel endogenous signalling systems with therapeutic significance.

Cannabinoids (CBs) are chemical compounds derived from cannabis.

This review discusses the basic science and clinical aspects of CB pharmacology with a focus on pain medicine.

Advances in cannabis research have ensured a future for these analgesic molecules which have been used since antiquity.”

http://bja.oxfordjournals.org/content/101/1/59.long

http://www.thctotalhealthcare.com/category/pain-2/

Evaluation of prevalent phytocannabinoids in the acetic acid model of visceral nociception.

Posted on April 27, 2015 by David

“Cannabis has been used for thousands of years as a therapeutic agent for pain relief, as well as for recreational purposes.

Delta-9-Tetrahydrocannabinol (Δ9-THC)… produces antinociceptive effects in a wide range of preclinical assays of pain.

Considerable preclinical research has demonstrated the efficacy of Delta(9)-tetrahydrocannabinol (Delta(9)-THC), the primary psychoactive constituent of Cannabis sativa, in a wide variety of animal models of pain, but few studies have examined other phytocannabinoids.

Indeed, other plant-derived cannabinoids, including cannabidiol (CBD), cannabinol (CBN), and cannabichromene (CBC) elicit antinociceptive effects in some assays. In contrast, tetrahydrocannabivarin (THCV), another component of cannabis, antagonizes the pharmacological effects of Delta(9)-THC.

These results suggest that various constituents of this plant may interact in a complex manner to modulate pain.

The primary purpose of the present study was to assess the antinociceptive effects of these other prevalent phytocannabinoids in the acetic acid stretching test, a rodent visceral pain model…

Importantly, the antinociceptive effects of Delta(9)-THC and CBN occurred at lower doses than those necessary to produce locomotor suppression, suggesting motor dysfunction did not account for the decreases in acetic acid-induced abdominal stretching.

These data raise the intriguing possibility that other constituents of cannabis can be used to modify the pharmacological effects of Delta(9)-THC by either eliciting antinociceptive effects (i.e., CBN) or antagonizing (i.e., THCV) the actions of Delta(9)-THC.

The results obtained in the present study are consistent with the view that Δ9-THC is the major phytocannabinoid present in marijuana that produces antinociception in the acetic acid abdominal stretching test.

…these results suggest that there is potential to develop medications containing various concentrations of specific phytocannabinoids to optimize therapeutic effects (e.g., antinociception) and minimize psychomimetic effects.

In sum, the results of the present study further support the notion that Δ9-THC is the predominant constituent of marijuana that is responsible for eliciting antinociceptive effects and indicate that CB1 receptors play a predominant role in mediating these effects.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2765124/

http://www.thctotalhealthcare.com/category/pain-2/

Intrathecal Injection of JWH-015 Attenuates Bone Cancer Pain Via Time-Dependent Modification of Pro-inflammatory Cytokines Expression and Astrocytes Activity in Spinal Cord.

Posted on April 22, 2015 by David

“Cannabinoid receptor type 2 (CB2) agonists display potential analgesic effects in acute and neuropathic pain.

Overall, our results provided evidences for the persistent participation of inflammation reaction in the progression of bone cancer pain, and demonstrated that JWH-015 reduced the expression of IL-1β, IL-6, IL-18, and TNF-α and inhibited astrocytes activation in a time-dependent manner, thereby displaying an analgesic effect.”

http://www.ncbi.nlm.nih.gov/pubmed/25896633

http://www.thctotalhealthcare.com/category/bone-cancer-2/

Attenuation of morphine antinociceptive tolerance by cannabinoid CB1 and CB2 receptor antagonists.

Posted on April 22, 2015 by David

“Cannabinoid CB1 and CB2 receptor antagonists may be useful for their potential to increase or prolong opioid analgesia while attenuating the development of opioid tolerance.

The aim of this study was to investigate the effects of AM251 (a selective CB1 antagonist) and JTE907 (a selective CB2 antagonist) on morphine analgesia and tolerance in rats…

In conclusion, we observed that co-injection of AM251 and JTE907 with morphine attenuated expression of tolerance to morphine analgesic effects and decreased the morphine analgesia.”

http://www.ncbi.nlm.nih.gov/pubmed/25894754

Historical essay: An Arabic surgeon, Ibn al Quff’s (1232-1286) account on surgical pain relief.

Posted on April 19, 2015 by David

“This is a review of Ibn al Quff’s account of surgical pain relief in his surgical book Al Omdah, in which he mentioned the word anesthetic (Al moukhadder) and the involvement of physician (al tabbaaee) to give mixture of drugs to prevent pain in a surgical condition to relieve the patient from pain or to make surgical management possible.

Hich indicated one rare occasion to such description in Arabic medical texts. Methods of administration of these drugs were inhalation, ingestion and by rectal suppositories.

The drugs used in anesthetic sponges include all the drugs that are recorded in the modern literature of anesthesia. They are as follows: opium, mandrake, Hyocymus albus, belladonna, Cannabis sativus, Cannabisindica, wild lettuce.

The anesthetic sponge, mentioned in many references as an inhalation method, may be of symbolic value to surgery.”

http://www.ncbi.nlm.nih.gov/pubmed/25885079

“Ibn al-Quff (1233-1286 AD), a medieval Arab surgeon and physician. Abū’l-Faraj ibn Ya’qūb ibn Isāq Ibn al-Quff al-Karakī (1233-1286 AD), best known as Ibn al-Quff in the West, was a 13th century Arab physician-surgeon. During his lifetime, Ibn al-Quff made some important contributions to the art of healing. He authored several books and commentaries in the field of medicine, in particular surgery.” http://www.ncbi.nlm.nih.gov/pubmed/24585631

http://www.thctotalhealthcare.com/category/pain-2/

Gonadal hormones do not alter the development of antinociceptive tolerance to delta-9-tetrahydrocannabinol in adult rats.

Posted on April 12, 2015 by David

“The purpose of this study was to determine whether sex differences in the development of antinociceptive tolerance to delta-9-tetrahydrocannabinol (THC) are due to activational effects of gonadal hormones…

These results suggest that greater antinociceptive tolerance in females, which occurred despite females receiving 40% less THC than males, is not due to activational effects of gonadal hormones.”

http://www.ncbi.nlm.nih.gov/pubmed/25863271

CB1 receptors modulate affective behaviour induced by neuropathic pain.

Posted on April 12, 2015 by David

“Patients suffering from chronic pain are often also diagnosed with a psychiatric condition, in particular generalized anxiety and major depression. The underlying pathomechanisms contributing to this comorbidity, however, are not entirely clear.

In this manuscript we have focussed on the potential role of the cannabinoid receptor CB1, because it is known to modulate neuronal circuits contributing to chronic pain states and affective behaviours.

For this purpose we analysed the consequences of a partial sciatic nerve ligation on anxiety- and depression related behaviours in mice lacking CB1 receptors.

Our results show that the development of mechanical hypersensitivity was similar in CB1 deficient mice and wild type controls. However, CB1 knockouts showed much more pronounced behavioural manifestations of anxiety-related behaviors in the light-dark and zero-maze tests, sucrose anhedonia, and disturbed home-cage activity.

These results indicate that the endocannabinoid system affects chronic pain-induced mood changes through CB1 receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/25863168

http://www.thctotalhealthcare.com/category/neuropathic-pain/

The role of the endocannabinoid system in pain.

Posted on April 8, 2015 by David

“Preparations of the Cannabis sativa plant have been used to analgesic effect for millenia, but only in recent decades has the endogenous system responsible for these effects been described.

The endocannabinoid (EC) system is now known to be one of the key endogenous systems regulating pain sensation, with modulatory actions at all stages of pain processing pathways.

The EC system is composed of two main cannabinoid receptors (CB1 and CB2) and two main classes of endogenous ligands or endocannabinoids (ECs).

The receptors have distinct expression profiles, with CB1 receptors found at presynaptic sites throughout the peripheral and central nervous systems (PNS and CNS, respectively), whilst CB2 receptor is found principally (but not exclusively) on immune cells.

The endocannabinoid ligands are lipid neurotransmitters belonging to either the N-acyl ethanolamine (NAEs) class, e.g. anandamide (AEA), or the monoacylglycerol class, e.g. 2-arachidonoyl glycerol (2-AG).

Both classes are short-acting transmitter substances, being synthesised on demand and with signalling rapidly terminated by specific enzymes. ECs acting at CB1 negatively regulate neurotransmission throughout the nervous system, whilst those acting at CB2 regulate the activity of CNS immune cells.

Signalling through both of these receptor subtypes has a role in normal nociceptive processing and also in the development resolution of acute pain states.

In this chapter, we describe the general features of the EC system as related to pain and nociception and discuss the wealth of preclinical and clinical data involving targeting the EC system with focus on two areas of particular promise: modulation of 2-AG signalling via specific enzyme inhibitors and the role of spinal CB2 in chronic pain states.”

http://www.ncbi.nlm.nih.gov/pubmed/25846617

http://www.thctotalhealthcare.com/category/pain-2/

Cannabinoids for the Treatment of Chronic Non-Cancer Pain: An Updated Systematic Review of Randomized Controlled Trials.

Posted on March 23, 2015 by David

“An updated systematic review of randomized controlled trials examining cannabinoids in the treatment of chronic non-cancer pain was conducted according to PRISMA guidelines for systematic reviews reporting on health care outcomes.

Eleven trials published since our last review met inclusion criteria.

The quality of the trials was excellent.

Seven of the trials demonstrated a significant analgesic effect.

Several trials also demonstrated improvement in secondary outcomes (e.g., sleep, muscle stiffness and spasticity).

Adverse effects most frequently reported such as fatigue and dizziness were mild to moderate in severity and generally well tolerated.

This review adds further support that currently available cannabinoids are safe, modestly effective analgesics that provide a reasonable therapeutic option in the management of chronic non-cancer pain.”

http://www.ncbi.nlm.nih.gov/pubmed/25796592

http://www.thctotalhealthcare.com/category/pain-2/

The role of cannabinoids in regulation of nausea and vomiting, and visceral pain.

Posted on February 27, 2015 by David

“Marijuana derived from the plant Cannabis sativa has been used for the treatment of many gastrointestinal (GI) disorders, including anorexia, emesis, abdominal pain, diarrhea, and others.

Several cannabinoid receptors, which include the cannabinoid receptor 1 (CB1), CB2, and possibly GPR55, have been identified throughout the GI tract.

These receptors may play a role in the regulation of food intake, nausea and emesis, gastric secretion and gastroprotection, GI motility, ion transport, visceral sensation, intestinal inflammation, and cell proliferation in the gut.

…the regulation of nausea and vomiting by cannabinoids and the endocannabinoid system has shed new knowledge in this field.

Novel drug targets such as FAAH and monoacylglycerol lipase (MAGL) inhibitors appear to be promising in animal models, but more studies are necessary to prove their efficiency.

The promise of emerging drugs that are more selective and peripherally acting suggest that, in the near future, cannabinoids will play a major role in managing an array of GI diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/25715910