Cannabis is illegal in the UK. Illegal drugs are classified, according to the extent of their health and social implications, as Class A, Class B or Class C (1). Class A drugs are considered the most harmful and carry the most severe sentences for both possession and trafficking while Class C drugs are considered the least dangerous and carry much lighter sentences. Cannabis, until now, has been classified as a Class B drug, carrying a sentence of up to five years for possession and fifteen years for trafficking. However, the downgrading of cannabis from a Class B drug to a Class C drug is set to go ahead on the 29th of January 2003. The government maintains that this is not synonymous to the legalisation of the drug (2), but the Home Secretary, David Blunkett, was ready to admit that in the majority of cases of the possession of cannabis, the police will merely “issue a warning and seize the drugs” (3). To assess whether or not the government should now take a final step and legalise the drug, it is important to firstly study the health impact of cannabis smoking on health as a whole and as compared to other harmful substances, such as alcohol and tobacco, which are currently legal and readily available.
Cannabis is a harmful drug. It can have harmful effects on the respiratory system, similar to those of tobacco smoking. It is widely accepted that cannabis can also make worse psychological disorders that are already present in the individuals concerned. Mood defects, such as paranoia and depression, can be worsened by the use of cannabis and short-term memory is also adversely affected.
The cardiovascular effects are an increase in the resting heart rate and increased blood pressure while sitting, but, a decreased blood pressure while standing. The change experienced when the user stands up after sitting can lead to a sensation of faintness and sometimes nausea. Cannabis can also reduce the reaction time in an individual, and this is important in road traffic accidents.
Four times the amount of tar can be deposited on the lungs from cannabis smoking than from tobacco smoking because tobacco smoking generally involves the use of filters while cannabis smoking does not. Chronic bronchitis symptoms are more prevalent in cannabis smokers than cannabis non-smokers and lung function is more likely to be impaired later in life if you are a cannabis smoker as opposed to a cannabis non-smoker. Studies at the genetic level have revealed that cannabis can be a major risk factor in the development of respiratory cancers and reports have suggested that extreme cannabis users have a greater incidence of gastrointestinal cancers, although cannabis smokers also are more likely to use other substances which increase the risk of developing these types of cancers, such as tobacco for the former and alcohol for the latter.
