Generally speaking, nausea and vomiting are our body’s defensive responses to the ingestion or digestion of potentially harmful substances. However, these events may be associated with the treatment of other diseases, as in the case of oncologic patientswho experience nausea as a response to chemotherapeutic drugs.
Although the use of medical Cannabis has a millennial origin in the fight against nausea and vomiting, it was only with the scientific discovery of Endocannabinoid System that the medical community has started to look more carefully at this practice.
Currently, there are several studies proving the potential of cannabinoids to fight nausea and vomiting of different causes. In this article, we will discuss the scientific evidence in this regard, with a focus on the anti-emetic potential of Cannabis in chemotherapy regimens.
The Endocannabinoid System in the physiology and pathophysiology of the gastrointestinal tract
With the expansion of research on Endocannabinoid System (ECS) as of the second half of the 20th century, the evidence on the therapeutic properties of Cannabis has been much better explained and explored.
Regarding the physiology and pathophysiology of the gastrointestinal tract, studies indicate that activation of CB1 receptors by cannabinoid substances can modulate a number of gastrointestinal functions, including gastric secretion, gastric emptying, and intestinal motility.
An example is this pre-clinical study, which through experimentally induced pathophysiological conditions in rodents, showed that the ECS confers protection to the gastrointestinal tract – regarding, for example, inflammation and abnormally high gastric and enteric secretions.
These results suggest that cannabinoid derivatives may be promising therapeutic targets in the treatment of different gastrointestinal disorders, including not only nausea and vomiting, but also inflammatory and functional bowel diseases, such as Crohn’s disease, irritable bowel syndrome, and disorders related to gastrointestinal secretion and motility.
>> You can read the full study here: The endocannabinoid system in the physiology and pathophysiology of the gastrointestinal tract..
Efficacy of Cannabis products for the treatment of nausea
Specifically regarding the treatment of nausea and vomiting, studies continue to show promise for the use of cannabinoids, such as this experiment which evaluated reports from 886 patients who completed 2,220 sessions of self-administration of Cannabis to treat nausea over a three-year period.
Using the Releaf App tool, patients recorded the characteristics of the self-administered Cannabis products and levels of symptom intensity. The results indicated that about an hour after consumption, 96.4 percent of people experienced symptom relief, with an average reduction of -3.85 points in nausea intensity (on a scale of 0 to 10).
The results also showed that Cannabis flowers and products with a higher concentration of cannabinoids performed better than hybrid products. In addition, extracts with higher THC (tetrahydrocannabinol) content compared to CBD (cannabidiol) were associated with greater relief in symptom intensity and also had a faster mechanism of action.
>> You can read the full experiment here: The Effectiveness of Common Cannabis Products for Treatment of Nausea.
Another research that brings promising results is this systematic review which evaluated 30 randomized studies evaluating the use of Cannabis, placebo or antiemetics, from records of information on efficacy and safety profile of the substance in data collected from 1,366 patients.
The study covered the following cannabinoid substances: oral nabilone, oral dronabinol and intramuscular levonantradol. The results showed that the antiemetic potential of these cannabinoids was superior to that of the following conventional antiemetics: prochlorperazine, metoclopramide, chlorpromazine, tiethylperazine, haloperidol, domperidone, and alizapride. Furthermore, in selected patients, the cannabinoids tested in these trials have been shown to be useful as an adjunctive treatment to improve mood in patients on a chemotherapy regimen. The most common adverse effects with cannabinoid use were euphoria, drowsiness, and prostration. Interesting to note in this study that most patients reported a preference for cannabinoid derivatives as antiemetic agents.
>> You can read the full study here: Cannabinoids for control of chemotherapy induced nausea and vomiting: quantitative systematic review.
Use of cannabinoids for the treatment of chemotherapy-induced nausea and vomiting
The anti-emetic potential is a well-known and well explored medicinal property of THC. Several studies,such as the one published by Meiri et al. (2007) have already shown a dramatic reduction in emesis associated with the use of synthetic cannabinoids such as dronabinol and nabilone. Not surprisingly, these cannabis-based drugs have been registered with the FDA in the US since the 1980s for the treatment of nausea and vomiting associated with chemotherapy.
Studies such as this systematic review with meta-analysis developed by the University of São Paulo (USP), compare the antiemetic efficacy of synthetic THC (dronabinol) and other cannabinoids in patients undergoing chemotherapy. The review used studies from several electronic databases, such as PUBMED, EMBASE, PSYCINFO and LILACS, and Cochrane.
The investigation evaluated 30 papers and 13 of them were used in the meta-analysis. All 30 papers demonstrated superiority of anti-emetic efficacy of cannabinoids compared to conventional drugs and placebo. In the meta-analysis, the drug groups evaluated were divided into 1) dronabinol versus placebo; 2) dronabinol versus neuroleptics; 3) nabilone versus neuroleptics; 4) levonantradol versus neuroleptics; 5) patient preference for Cannabis or other drugs.
The cannabinoid dronabinol showed superior anti-emetic efficacy over neuroleptics for cancer patients on a chemotherapy regimen. Although the other comparisons were not significantly different, clinical differences were found. Patients showed a clear preference for cannabinoids as antiemetic agents when receiving chemotherapy drugs.
>>You can read the full research here: Therapeutic use of Cannabis sativa on chemotherapy-induced nausea and vomiting among cancer patients: systematic review and meta-analysis.
We also point out this case study, which evaluated the use of dronabinol in the treatment of nausea and vomiting resulting from radiation therapy treatment. The study investigates the condition of a 50-year-old man who, four years after resection of a Clark’s level IV malignant melanoma, developed metastatic disease involving the liver, bones, brain, gastrointestinal mucosa, and lungs.
The patient, who underwent brain radiation therapy, was treated with several conventional antiemetic drugs, but showed no signs of improvement. However, the use of dronabinol showed much better results than these drugs in fighting nausea and vomiting probably due to metastasis of the gastrointestinal mucosa.
The results suggest that, especially in conditions where patients do not respond to conventional antiemetics, a combination of dronabinol and prochlorperazine tends to be an effective antiemetic therapy.
>> You can read the full study here: Intractable nausea and vomiting due to gastrointestinal mucosal metastases relieved by tetrahydrocannabinol (dronabinol).
Use of cannabinoids for treatment of nausea and vomiting associated with Hyperemesis gravidarum
Although we still have no scientific studies attesting to the safety of the use of cannabinoid derivatives in pregnant women, especially regarding the health of the fetus, there are conclusive reports of the antiemetic potential of Cannabis also in the context of hyperemesis gravidarum.
This is what this Israeli study demonstrated, which evaluated four women with severe and refractory Hyperemesis Gravidarum before and after Cannabis use, using the PUQE (Pregnancy Unique Quantification of Emesis) Score. There was a highly significant improvement in symptoms: the PUQE score improved from 14.5 to 7.5 (p = 0.0004) and Cannabis use was also associated with a significant improvement in quality of life on the PUQE Quality of Life scale.
The authors conclude that Cannabis can be effective in the management of Hyperemesis Gravidarum and that this therapeutic tool should be rigorously evaluated through randomized controlled studies to make a careful analysis about the potential risks to the fetus.
>> You can read the full study here:
Other cannabinoids in the treatment of nausea and vomiting
In addition to the THCscientific studies also cover other cannabinoids that show anti-emetic potential. In this literature reviewin vitro and in vivo studies were evaluated for the efficacy of cannabidiol (CBD), from cannabidiolic acid (CBDA) and a methylated version of CBDA (CBDA-ME) in the treatment of nausea and vomiting.
The results showed that while CBD was effective in controlling these clinical pictures, CBDA and CBDA-ME were more potent in their ability to reduce nausea and vomiting.
>> You can read the full study here: Therapeutic Potential of Cannabidiol, Cannabidiolic Acid, and Cannabidiolic Acid Methyl Ester as Treatments for Nausea and Vomiting.
While the scientific evidence surrounding the use of cannabinoids to treat nausea and vomiting is numerous, specialized training in the field is imperative to safely incorporate medical Cannabis into prescriptive practices in order to potentiate therapeutic outcomes and modulate potential adverse effects in treatments.
The WeCann Academy is committed to your learning journey through the International Certification in Endocannabinoid Medicine. We provide disruptive knowledge to physicians who wish to incorporate cannabinoid derivatives into their prescriptive practice and achieve better outcomes with their patients.
We connect experts from around the world in a global Endocannabinoid System study community to bridge scientific knowledge and practical experience in the medical use of Cannabis.
Would you like to join us? Contact us and get ready for this new frontier of Medicine!
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Machado Rocha FC, Stéfano SC, De Cássia Haiek R, Rosa Oliveira LM, Da Silveira DX. Therapeutic use of Cannabis sativa on chemotherapy-induced nausea and vomiting among cancer patients: systematic review and meta-analysis. Eur J Cancer Care (Engl). 2008.
Massa F, Storr M, Lutz B. The endocannabinoid system in the physiology and pathophysiology of the gastrointestinal tract.. J Mol Med (Berl). 2005.
Meiri E, Jhangiani H, Vredenburgh JJ, Barbato LM, Carter FJ, Yang HM, Baranowski V. Efficacy of dronabinol alone and in combination with ondansetron versus ondansetron alone for delayed chemotherapy-induced nausea and vomiting. Curr Med Res Opin. 2007.
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Stith SS, Li X, Orozco J, Lopez V, Brockelman F, Keeling K, Hall B, Vigil JM. The Effectiveness of Common Cannabis Products for Treatment of Nausea. J Clin Gastroenterol. 2022.
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