Cannabis sativa and derived substances from this hallucinogen have been a part of human cultures for centuries, being used at initiation rituals and religious ceremonies. In the last two centuries there has been change in its use, through several tries in making it an over the counter medicine (in the 19th century, for treatment of coughs and respiratory illnesses), and as a recreational drug in the 20th and 21st century .
It is currently one of the most popular illicit drugs in use, mainly by adolescent and young adult populations of both sexes, regardless of economic and social status [1,2]. Its rise in consumption and civil pressure by a number of different actors have lead to legalization of production, sale and consumption of marijuana products in some countries and territories, such as Holland, Uruguay, California and Colorado in the United States of America. The main arguments used for justifying such measure was the 1) reduction of crime, 2) the relative harmlessness of cannabinoid products, especially when compared with other legal drugs in circulation such as alcohol and cigarettes, and 3) individual affirmation of the right of consume any form of substance.
Evidence from scientific studies, however, do not support these statements. In a longitudinal study conducted in England and Wales, following the depenalisation of marijuana use in these countries, from 2003 up to 2006, criminal activities statistics were analyzed and compared with other decades’. Although the study did not find a rise in crime following the decriminalization, it did not document any fall in criminality of any sort .
Several cohort studies have pointed to negative effects of recreational use of marijuana, whether by predisposing users to mental illness, psychotic episodes, major depression and other drugs abuse and addiction . Somatic diseases have also been discovered and linked to chronic use of Cannabis, such as pulmonary emphysema, airway irritation and precancerous lesions comparable to tobacco user’s findings .
Also, prolonged or heavy use of marijuana has been positively linked to decline in cognitive skills, memory processing and task accomplishments, possibly due to neuron death. This is indirectly responsible for greater incidence of motor vehicle crashes, school default and Cannabis dependence (with incidence of 7-10% amongst chronic users) [5,6]. In sum, there is sufficient data to determine cannabis recreational use brings several important consequences to individual health, and therefore to public health policies, to a similar extent of alcohol and nicotine. No evidence has emerged that its use is innocuous, and the effects of its legalization on criminality and improvement of safety condition is almost nonexistent .
Countries and societies need to consider possible outcomes of decriminalization of cannabinoid substances, as this measure is sure to be followed by increase in consumption, and therefore by greater incidence of all maladies caused by chronic consumption.