Gateway drugs

If is often claimed that cannabis is a gateway drug in that its use leads to use of drugs like heroin or cocaine. Although the bulk of heroin and cocaine users have used cannabis the vast majority of people who have used cannabis have never used heroin or cocaine. 

Social factors such as peer pressure at school or work as well as family patterns of substance use can also contribute to the risk. Teenagers who respond to pressure to use gateway drugs such as alcohol, tobacco, and marijuana in their early teens are more likely to develop substance dependence disorders than those who refrain from doing so until their late teens. 

Clearly is often a gateway drug , although many use only this... 

Gateway drug—Theory of drug enforcers who argue that even if Marijuana is not in the same class as certain narcotics, it should be treated the same way because it introduces people, especially the young, to those "harder" drugs. 

Hall, W. D., Lynskey, M. (2005). Is cannabis a gateway drug Testing hypotheses about the relationship between cannabis use and the use of other illicit drugs. Dru and Alcohol Review, 24, 39-48. 

In my opinion, there is a gateway drug, but it is not marijuana. It is nicotine, most commonly delivered in the form of cigarettes. Young people who do not smoke have been found to be far less likely to try other drugs and not to become heavy users of alcohol than those who smoked (according to the 1998 National Household Survey on Drug Abuse). 

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