Cannabinoid adverse effects

Ashton CH (1999). Adverse effects of cannabis and cannabinoids. British Journal of Anaesthesia, 83, 637-649. 

Adverse effects Its adverse effects include severe nausea and vomiting (centrally mediated). [Note These effects can be diminished by pretreatment with cannabinoids (see p. 243) or pheno-thiazine (see p. 242).] Severe bone marrow depression limits extensive use. Latent viral infections (for example, Herpes zoster] may appear because of immunosuppression. Extravasation is a serious problem. If it occurs, the area should be infiltrated with isotonic sodium thiosulfite to inactivate the drug. 

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). 

Concerns have been raised about the possible adverse effects of acute as well as chronic medicinal and recreational use of cannabis on cognition and the body (104). The author, while acknowledging the therapeutic role of cannabinoids in the management of pain and other conditions, expressed concern that in recent years the prevalence of recreational cannabis use (especially in the young) and the potency of the available products have markedly increased in the UK. 

Nabilone is a synthetic cannabinoid and has properties similar to tetrahydrocannabinol (the active constituent of marijuana) which has an antiemetic action. It is used to relieve nausea or vomiting caused by cytotoxic drugs. Adverse effects include somnolence, dry mouth, decreased appetite, dizziness, euphoria, dysphoria, postural hypotension, confusion and psychosis. These may be reduced if prochlorperazine is given concomitantly. 

Adverse effects of cannabinoids, and in particular of THC, on reproductive functions include retarded embryo development, foetal loss and pregnancy failure. They have been known for a long time (Geber and Schramm 1969 Kolodney et al. 1974 Das et al. 1995 Ness et al. 1999), and were recently reviewed (Paria and Dey 2000 Maccarrone et al. 2002). 

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. 

Sarafian TA, Magallanes JA, Shau H, et al. Oxidative stress produced by marijuana smoke An adverse effect enhanced by cannabinoids. Am J RespirCell Mol Biol 1999 20 1286-1293. 

These findings suggest possible roles for AEA signaling via CBRs in modulating sperm production and may account, at least in part, for the adverse effects of marijuana smoke and cannabinoids on sperm production in humans and laboratory animals (Schuel et al., 1999 Schuel et al., 2002a). 

Adverse events observed with nonselective agonists may not be as common or pronounced with peripherally selective CB cannabinoids. They include potential for abuse, confusion, ataxia, memory loss, psychosis, dizziness, hypotension, sedation, euphoria, paranoia, and dry mouth. Less common adverse events include orthostatic hypotension, abdominal pain, nausea, vomiting, anxiety, myalgias, increased appetite, nightmares, flushing, visual difficulties, and headache. No specific antagonists are currently in use, but adverse effects can be cared for individually. 

Wang T, Collet J, Shapiro S, Ware MA. Adverse effects of medical cannabinoids a systematic review. CMAJ 2008 178(13) 1669-78. 

Synthetic cannabinoids have become popular recreational drugs of abuse and many of them have been banned in United States due to their potentially harmful adverse effects, which are often less well known. Anew case report discusses outcome following K9 abuse [IS ]. 

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