Adverse effects cannabis

It has been suggested that MDMA and cannabis are soft drugs without many adverse effects. Do you agree (Note this question also applies to Chapter 7.)... 

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

Hall W and Solowij N (1998). Adverse effects of cannabis. Lancet, 352, 1611-1616. 

Adverse effects. A causal role of acute cannabis intoxication in motor vehicle and other accidents has been shown by the pres-... 

Kalant, H. Adverse effects of cannabis on health an update of the literature since 1996. Prog Neuropsych-opharmacol Biol Psychiatry 2004 28(5) 849-863. 

The psychological and physical adverse effects of cannabis have been the subject of many studies, with psychological ones in particular much debated (Hall Solowij 2006). The suspicion of an amotivational syndrome has not exactly gone away, but it seems such an... 

Hall, Wayne, and Nadia Solowij. Adverse effects of cannabis. The Lancet 352 1611-1616, 1998. 

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). 

Of 220 patients with multiple sclerosis in Halifax, Canada 72 (36%) reported ever having used cannabis (56). Ever use of cannabis for medicinal purposes was associated with male sex, the use of tobacco, and recreational use of cannabis. Of the 34 medicinal cannabis users, 10 reported mild, eight moderate and one strong adverse effects none reported severe adverse effects. The most common adverse effects were feeling high (n = 24), drowsiness (20), dry mouth (14), paranoia (3), anxiety (3), and palpitation (3). 

A review has summarized the evidence related to the adverse effects of acute and chronic use of cannabis (60). The effects of acute usage include anxiety, impaired attention, and increased risk of psychotic symptoms. Probable risks of chronic cannabis consumption include bronchitis and subtle impairments of attention and memory. 

Hypersensitivity reactions are rare, but a few have been reported after inhalation. Delayed hypersensitivity reactions, particularly affecting vascular tissue, have been recorded with chronic systemic administration. Tumor-inducing effects are difficult to attribute to cannabis alone. Animal studies have shown neoplastic pulmonary lesions superimposed on chronic inflammation, but such pathology may be primarily associated with the tar produced by burning marijuana. The most serious potential adverse effects of cannabis use come from the inhalation of the same carcinogenic hydrocarbons that are present in tobacco, and some data suggest that heavy cannabis users are at risk of chronic respiratory diseases and lung cancer. 

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. 

Russo E, Mathre ML, Byrne A, Velin R, Bach PJ, Sanchez-Ramos J, Kirlin KA. Chronic cannabis use in the compassionate investigational new drug program an examination of benefits and adverse effects of legal clinical cannabis. J Cannabis Ther 2002 2 3-57. 

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