The Toxicology of Cannabis and Cannabis Prohibition

Abstract

The acute side effects caused by cannabis use are mainly related to psyche and cognition, and to circulation. Euphoria, anxiety, changes in sensory perception, impairment of memory and psychomotor performance are common effects after a dose is taken that exceeds an individually variable threshold. Cannabis consumption may increase heart rate and change blood pressure, which may have serious consequences in people with heart disease. Effects of chronic use may be induction of psychosis and development of dependency to the drug. Effects on cognitive abilities seem to be reversible after abstinence, except possibly in very heavy users. Cannabis exposure in utero may have negative consequences on brain development with subtle impairment of cognitive abilities in later life. Consequences of cannabis smoking may be similar to those of tobacco smoking and should be avoided. Use by young people has more detrimental effects than use by adults. There appear to be promising therapeutic uses of cannabis for a range of indications. Use of moderate doses in a therapeutic context is usually not associated with severe side effects. Current prohibition on cannabis use may also have harmful side effects for the individual and the society, while having little influence on prevalence of use. Harm is greatest for seriously ill people who may benefit from a treatment with cannabis. This makes it difficult to justify criminal penalties against patients.

Health Policy for Marijuana

“…Most of the medical knowledge and uses related to marijuana are derived from cannabinoids, and not the smoked or edible marijuana itself. Naturally occurring marijuana or THC has not been extensively researched for its health benefits and its effectiveness as a medication is not supported by existing research [5,8].…”

“…Furthermore, marijuana frequently causes and induces anxiety and depression in the users, which might be brief panic reactions but long lasting psychiatric symptomatology is described [22]. Marijuana impairs the capacity for the users to properly operate machinery, vehicles, and under the influence of cannabis, higher rates of traffic accidents and deaths are reported [5,8,23,[46][47][48].…”

“…The risk of suffering an acute cardiac event is increased 5-fold for previously healthy individuals and even higher for users with pre-existing cardiac conditions [8]. Marijuana also causes a reduced blood flow in the brain by increasing the cerebrovascular resistance and systolic velocity significantly compared to non-users [7].…”

Cannabis and Its Derivatives: Review of Medical Use

“…16 The estimated lethal dose for humans is between 15 g and 70 g. 3 When compared with cigarette smoke, cannabis contains a similar array of detrimental and carcinogenic compounds, some of which are present even at higher concentrations. 17 Among chronic users, population studies have associated cannabis use with decreased pulmonary function, chronic obstructive airway diseases, and pulmonary infections, 18 although data may be confounded by concomitant tobacco smoking and other social factors. In vitro and in vivo animal studies have demonstrated mutagenic effects of cannabis smoke, and precancerous pulmonary pathology as seen in tobacco smokers has been described in cannabis users.…”

Impact of repeated administration of Cannabis sativa on some biochemical parameters in albino rats

“…After, cannabis usage, a sudden change of posture from lying down to standing up may produce orthostatic hypotension, a feeling of 'light-headedness' and faintness that is often the earliest indication of intoxication in naive users [9]. Other physical effects of cannabis include reddening of the eyes due to congestion of the conjunctiva blood vessels, lowering of the body temperature, dry mouth, reduced intraocular pressure and relaxation of the muscles [10]. Cannabinoids have also been shown to affect the immune system [11].Clinical studies and survey data have found that cannabis increases appetite [12].…”