Cannabis antiemetic effects

Dronabinol (tetrahydrocannabinol), the active principle from cannabis and synthetic cannabinoids, nabilone and levonantradol are effective in treating nausea and vomiting in cancer chemotherapy. The mode of action is unclear but appears to involve cannabinoid CBi receptors. Cannabinoids have been shown to reduce acetylcholine release in the cortex and hippocampus, and have been suggested to inhibit medullary activity by a cortical action. Inhibition of prostaglandin synthesis and release of endorphins may also be involved in the antiemetic effect. A review of trials of dronabinol, nabilone or levonantradol concluded that while the cannabinoids were superior to placebo or dopamine receptor antagonists in controlling emesis... 

Plasse T (1984) Antiemetic effects of cannabinoids. In Grotenhermen F, Russo E (eds) Cannabis and cannabinoids. Pharmacology, toxicology, and therapeutic potential. The Haworth Integrative Healing Press, New York, pp 165-180... 

O Shaughnessy WB (1843) On the cannabis indica or Indian hemp. Pharmacol J 2 594 Orr LE, McKernan JF (1981) Antiemetic effect of delta-9-THC in chemotherapy-associated... 

As noted above, Cannabis was used as an antiemetic drug in antiquity it was used in India as such for hundreds of years (and its use probably still continues in popular medicine) and was well known to physicians in England during the 19th century. Yet, the discovery of the antiemetic effects of A -THC in 1975 was serendipitous and followed street reports that marihuana helped to overcome the side-effects of anticancer chemotherapy [147]. The original... 

Cannabis resin, obtained from the flowering tops of hemp plants, contains a number of dibenzopyrans. The main active constituent is (-)-A1-3,4-numbering system is used). Cannabinol derivatives have slight pharmaceutical potential, e.g. as antiemetics and analgesics, but because of their hallucinatory effects and habituation tendency, which have led to their widespread abuse, they are not prescribed. 

A9-Tetrahydrocannabinol is the major psychoactive cannabinoid in marijuana (Cannabis sativa). Its synthetic form, dronabinol, became available in the U.S. in 1985 as an antiemetic for patients receiving emetogenic chemotherapy. However, it is seldom used as a first-line antiemetic because of its psychoactive effects, and its use is usually limited to patients who have a low tolerance or minimal response to other antiemetic drugs (see Chapter 18). 

Cannabis is one of the oldest and most widely used drugs in the world. In different Western countries the possible therapeutic use of cannabinoids as antiemetics in patients with cancer or in patients with multiple sclerosis has become an issue, because of the prohibition of cannabis, and has polarized opinion about the seriousness of its adverse effects (1,2). 

Cannabis and THC synthetics have Iwen used to counter the nausea and vomiting frequently associated with chemotherapies (and some radiation treatments) for cancer. These side effects, which can last for several hours or even several days, often are not ameliorated by traditional antiemetic medications (although significant advances arc being made in the development of more powerful antisickness drugs). Researchers in... 

Thirty randomized, controlled trials from 1975 to 1996 were analyzed to quantify the antiemetic efficacy and adverse effects of cannabis when given to 1366 patients receiving chemotherapy. Oral nabUone, oral dronabinol, and intramuscular levonantradol were compared with conventional antiemetics (prochlorperazine, metoclopramide, chlor-promazine, thiethylperazine, haloperidol, domperidone, and aliza-pride) or placebo. Across all trials, cannabinoids were slightly more effective than active comparators and placebo when the chemotherapy regimen was of moderate emetogenic potential, and patients preferred them. No dose-response relationships were evident to the authors. The cannabinoids were also more toxic side effects included euphoria, drowsiness, sedation, somnolence, dysphoria, depression, hallucinations, and paranoia. The efficacy of cannabinoids as compared to SSRls has not been studied. Use of these agents should be considered when other regimens do not provide desired efficacy. 

Cannabis has been used as an analgesic and A -THC is a potent antiemetic and the drug has also been used as a remedy for glaucoma and in multiple sclerosis. The side-effects have, however, limited the drug in its... 

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