Delta-9-tetrahydrocannabinol in cancer chemotherapy: research problems and issues.

Abstract

“A critical review of the literature assessing the antiemetic efficacy of delta-9-tetrahydrocannabinol (THC) in patients receiving cancer chemotherapy showed considerable inconsistency in results. The equivocal nature of these results partly reflects the difficulty of doing research on antiemetic therapies, but also can be attributed to differences in the adequacy and nature of the research designs, procedures, and assessment instruments that have been used. Several factors were also identified that are seldom studied but may be important in determining whether THC will be effective: patient variables, such as chemotherapy regimen and age; pharmacologic variables, such as drug tolerance, dose, schedule, toxicity, route of administration, and drug interactions; and environmental variables associated with administration setting. The need to differentiate pharmacologically induced from conditioned nausea and vomiting was also pointed out. We believe that THC does have antiemetic efficacy, but the lack of controlled research does not allow precise knowledge of its true effectiveness and toxicity. Well-controlled trials are needed to help answer some of these questions.”

http://www.ncbi.nlm.nih.gov/pubmed/6305249

Antiemetic effect of tetrahydrocannabinol. Compared with placebo and prochlorperazine in chemotherapy-associated nausea and emesis.

Abstract

“Fifty-five patients harboring a variety of neoplasms and previously found to have severe nausea or emesis from antitumor drugs were given antiemetic prophylaxis in a double-blind, randomized, crossover fashion. Tetrahydrocannabinol (THC), prochlorperazine, and placebo were compared. Nausea was absent in 40 of 55 patients receiving THC, eight of 55 patients receiving prochlorperazine, and five of 55 in the placebo group.

The antiemetic effect of THC appeared to be more efficacious for cyclophosphamide, fluorouracil, and doxorubicin hydrochloride, and less so for mechlorethamine hydrochloride and the nitrosureas.

Tetrahydrocannabinol appears to offer significant control of nausea in most patients and exceeding by far that provided by prochlorperazine.”

http://www.ncbi.nlm.nih.gov/pubmed/6254456

 

Amelioration of cancer chemotherapy-induced nausea and vomiting by delta-9-tetrahydrocannabinol.

Abstract

“The antinausea and antivomiting effects of delta-9-tetrahydrocannabinol (THC) in children receiving cancer chemotherapy were compared with those of metoclopramide syrup and prochlorperazine tablets in two double-blind studies. THC was found to be a significantly better antinausea and antivomiting agent… In some patients, THC enhanced appetite during a course of chemotherapy. In two patients, a “high” associated with THC administrationwas reported. Drowsiness was reported significantly more frequently with THC.”

http://www.ncbi.nlm.nih.gov/pubmed/231736

Preliminary efficacy and safety of an oromucosal standardized cannabis extract in chemotherapy-induced nausea and vomiting

  “Despite progress in anti-emetic treatment, many patients still suffer from chemotherapy-induced nausea and vomiting (CINV). This is a pilot, randomized, double-blind, placebo-controlled phase II clinical trial designed to evaluate the tolerability, preliminary efficacy, and pharmacokinetics of an acute dose titration of a whole-plant cannabis-based medicine (CBM) containing delta-9-tetrahydrocannabinol and cannabidiol, taken in conjunction with standard therapies in the control of CINV.”

“Compared with placebo, CBM added to standard antiemetic therapy was well tolerated and provided better protection against delayed CINV. These results should be confirmed in a phase III clinical trial.”

“A systematic review of 30 clinical trials involving orally administered synthetic cannabinoids (nabilone and dronabinol) showed that they were superior to dopamine receptor antagonists in preventing CINV. Both are approved by the US Food and Drug Administration for use in CINV refractory to conventional anti-emetic therapy, but some authors have questioned the appropriateness of orally administered cannabinoids due to the variability in their gastrointestinal absorption, low bioavailability, long half-lives and the difficulties for an adequate self titration of the dose.”

“Animal studies suggest that the combined administration of different cannabinoids may enhance some of the therapeutic effects of delta-9-tetrahydrocannabinol (THC). This might explain why some patients preferred marihuana to synthetic cannabinoids in clinical trials.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2997305/

Efficacy of Crude Marijuana and Synthetic Delta-9-Tetrahydrocannabinol as Treatment for Chemotherapy-Induced Nausea and Vomiting: A Systematic Literature Review.

Abstract

“Purpose/Objectives: To synthesize the research to determine whether oral delta-9-tetrahydrocannabinol (THC) and smoked marijuana are effective treatments for chemotherapy-induced nausea and vomiting (CINV) and to evaluate side effects and patient preference of these treatments.Data Sources: Original research, review articles, and other published articles in CINAHL(R), MEDLINE(R), and Cochrane Library databases.Data Synthesis: Cannabinoids are effective in controlling CINV, and oral THC and smoked marijuana have similar efficacy. However, smoked marijuana may not be accessible or safe for all patients with cancer. Also, these drugs have a unique side-effect profile that may include alterations in motor control, dizziness, dysphoria, and decreased concentration.Conclusions: This synthesis shows that cannabinoids are more effective than placebo and comparable to antiemetics such as prochlorperazine and ondansetron for CINV.Implications for Nursing: Nurses should feel supported by the literature to recommend oral synthetic THC as a treatment for CINV to their patients and physician colleagues. Nurses should be cognizant of the side-effect profile for this medication and provide appropriate patient education.”

http://www.ncbi.nlm.nih.gov/pubmed/19596652

Review of cannabinoids and their antiemetic effectiveness.

Abstract

“Marijuana has been used for over 2 centuries. Its major psychoactive constituent, delta-9-tetrahydrocannabinol (THC) was isolated in 1964 and first used to control nausea and vomiting during chemotherapy in the 1970s. THC has cardiovascular, pulmonary and endocrinological effects as well as actions on the central nervous system. Alterations in mood, memory, motor coordination, cognitive ability, sensorium, spatial- and self-perception are commonly experienced. The precise antiemetic mechanism is unknown. THC and nabilone act at a number of sites within the central nervous system. Cannabinoids have also been shown to inhibit prostaglandin synthesis in vitro. In controlled clinical trials, THC is superior to placebo and prochlorperazine in antiemetic effectiveness. Effectiveness of THC correlates to a ‘high’ experienced by the patient. A variety of chemotherapy regimens respond to THC including high-dose methotrexate and the doxorubicin, cyclophosphamide, fluorouracil combination. Cisplatin is more resistant. Side effects are generally well tolerated but may limit THC use in the elderly or when high doses are administered. Nabilone, a synthetic cannabinoid, is also an effective antiemetic which is more active than prochlorperazine in preventing chemotherapy-induced emesis, including cisplatin-containing regimens. Side effects are similar to THC and may be dose-limiting. Levonantradol, another synthetic cannabinoid, is an effective antiemetic. It may provide more flexibility in the outpatient setting since it can be administered orally or intramuscularly. Most side effects are mild except for dysphoria which may be dose-limiting.”

http://www.ncbi.nlm.nih.gov/pubmed/6301800

Therapeutic use of Cannabis sativa on chemotherapy-induced nausea and vomiting among cancer patients: systematic review and meta-analysis.

Abstract

“This paper aims to evaluate the anti-emetic efficacy of cannabinoids in cancer patients receiving chemotherapy using a systematic review of literature searched within electronic databases such as PUBMED, EMBASE, PSYCINFO, LILACS, and ‘The Cochrane Collaboration Controlled Trials Register’. Studies chosen were randomized clinical trials comprising all publications of each database until December 2006. From 12 749 initially identified papers, 30 fulfilled the inclusion criteria for this review, with demonstration of superiority of the anti-emetic efficacy of cannabinoids compared with conventional drugs and placebo. The adverse effects were more intense and occurred more often among patients who used cannabinoids. Five meta-analyses were carried out: (1) dronabinol versus placebo [n=185; relative risk (RR)=0.47; confidence interval (CI)=0.19-1.16]; (2) Dronabinol versus neuroleptics [n=325; RR=0.67; CI=0.47-0.96; number needed to treat (NNT)=3.4]; (3) nabilone versus neuroleptics (n=277; RR=0.88; CI=0.72-1.08); (4) levonantradol versus neuroleptics (n=194; RR=0.94; CI=0.75-1.18); and (5) patients’ preference for cannabis or other drugs (n=1138; RR=0.33; CI=0.24-0.44; NNT=1.8). The superiority of the anti-emetic efficacy of cannabinoids was demonstrated through meta-analysis.”

http://www.ncbi.nlm.nih.gov/pubmed/18625004

Cannabinoids in the treatment of chemotherapy-induced nausea and vomiting: beyond prevention of acute emesis.

Abstract

“Chemotherapy-induced nausea and vomiting (CINV) remains a significant problem in the care of cancer patients. Although the use of serotonin (5-HT3) receptor antagonists, as well as neurokinin-1 inhibitors, has reduced rates of acute emesis, many patients still experience acute vomiting; moreover, these agents have reduced efficacy in preventing nausea, delayed CINV, and breakthrough CINV. Nausea, in particular, continues to have a major–and often overlooked–impact on patients’ quality of life. Optimizing the treatment for CINV likely will involve combinations of agents that inhibit the numerous neurotransmitter systems involved in nausea and vomiting reflexes. Cannabinoids are active in many of these systems, and two oral formulations, dronabinol (Marinol) and nabilone (Cesamet), are approved by the US Food and Drug Administration for use in CINV refractory to conventional antiemetic therapy. Agents in this class have shown superiority to dopamine receptor antagonists in preventing CINV, and there is some evidence that the combination of a dopamine antagonist and cannabinoid is superior to either alone and is particularly effective in preventing nausea. The presence of side effects from the cannabinoids may have slowed their adoption into clinical practice, but in a number of comparative clinical trials, patients have expressed a clear preference for the cannabinoid, choosing its efficacy over any undesired effects. Improvement in antiemetic therapy across the entire spectrum of CINV will involve the use of agents with different mechanisms of action in concurrent or sequential combinations, and the best such combinations should be identified. In this effort, the utility of the cannabinoids should not be overlooked.”

http://www.ncbi.nlm.nih.gov/pubmed/17566383

Regulation of nausea and vomiting by cannabinoids.

“Anti-emetic effects of cannabinoids in human clinical trials”

  “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. CB1 agonism suppresses vomiting, which is reversed by CB1 antagonism, and CB1 inverse agonism promotes vomiting. 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. Although rats and mice are incapable of vomiting, they display a distinctive conditioned gaping response when re-exposed to cues (flavours or contexts) paired with a nauseating treatment. Cannabinoid agonists (Δ9-THC, HU-210) and the fatty acid amide hydrolase (FAAH) inhibitor, URB-597, suppress conditioned gaping reactions (nausea) in rats as they suppress vomiting in emetic species. Inverse agonists, but not neutral antagonists, of the CB1 receptor promote nausea, and at subthreshold doses potentiate nausea produced by other toxins (LiCl). The primary non-psychoactive compound in cannabis, cannabidiol (CBD), also suppresses nausea and vomiting within a limited dose range. The anti-nausea/anti-emetic effects of CBD may be mediated by indirect activation of somatodendritic 5-HT1A receptors in the dorsal raphe nucleus; activation of these autoreceptors reduces the release of 5-HT in terminal forebrain regions. Preclinical research indicates that cannabinioids, including CBD, may be effective clinically for treating both nausea and vomiting produced by chemotherapy or other therapeutic treatments.”

“The cannabis plant has been used for several centuries for a number of therapeutic applications, including the attenuation of nausea and vomiting. Ineffective treatment of chemotherapy-induced nausea and vomiting prompted oncologists to investigate the anti-emetic properties of cannabinoids in the late 1970s and early 1980s, before the discovery of the 5-HT3 antagonists. The first cannabinoid agonist, nabilone (Cesamet), which is a synthetic analogue of Δ9-THC was specifically licensed for the suppression of nausea and vomiting produced by chemotherapy. Furthermore, synthetic Δ9-THC, dronabinol, entered the clinic as Marinol in 1985 as an anti-emetic and in 1992 as an appetite stimulant. In these early studies, several clinical trials compared the effectiveness of Δ9-THC with placebo or other anti-emetic drugs. Comparisons of oral Δ9-THC with existing anti-emetic agents generally indicated that Δ9-THC was at least as effective as the dopamine antagonists, such as prochlorperazine.”

“There is some evidence that cannabis-based medicines may be effective in treating the more difficult to control symptoms of nausea and delayed nausea and vomiting in children. Abrahamov et al. (1995) evaluated the anti-emetic effectiveness of Δ8-THC, a close but less psychoactive relative of Δ9-THC, in children receiving chemotherapy treatment. Two hours before the start of each cancer treatment and every six hours thereafter for 24 h, the children were given Δ8-THC as oil drops on the tongue or in a bite of food. After a total of 480 treatments, the only side effects reported were slight irritability in two of the youngest children (3.5 and 4 years old); both acute and delayed nausea and vomiting were controlled.”

“Chemotherapy-induced vomiting is well controlled in most patients by conventionally available drugs, nausea (acute, delayed and anticipatory) continues to be a challenge. Nausea is often reported as more distressing than vomiting, because it is a continuous sensation. Indeed, this distressing symptom of chemotherapy treatment (even when vomiting is pharmacologically controlled) can become so severe that as many as 20% of patients discontinue the treatment. Both preclinical and human clinical research suggests that cannabinoid compounds may have promise in treating nausea in chemotherapy patients.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3165951/

Mechanism of action of cannabinoids: how it may lead to treatment of cachexia, emesis, and pain.

Image result for The Journal of Supportive Oncology

“Many patients with life-threatening diseases such as cancer experience severe symptoms that compromise their health status and deny them quality of life. Patients with cancer often experience cachexia, pain, and depression,which translate into an unacceptable quality of life. The discovery of the endocannabinoid system has led to a renewed interest in the use of cannabinoids for the management of nausea, vomiting, and weight loss arising either from cancer or the agents used to treat cancer. The endocannabinoid system has been found to be a key modulator of systems involved in pain perception, emesis, and reward pathways. As such, it represents a target for development of new medications for controlling the symptoms associated with cancer. Although the cannabinoid receptor agonist tetrahydrocannabinol and one of its analogs are currently the only agents approved for clinical use, efforts are under way to devise other strategies for activating the endocannabinoid system for therapeutic uses.”

http://www.ncbi.nlm.nih.gov/pubmed/15357514