Despite growing acceptance of medical marijuana, there are still those who view cannabis as a "gateway" drug which would only exacerbate substance abuse. In fact, the body of evidence seems to suggest the opposite.
As long ago as 1889, physicians were recommending cannabis over opiates as a therapeutic drug, both for its quality of effect and it's lack of addictive consequences. Over the ensuing decades, cannabis fell into disrepute as a recreational rather than a medicinal drug.
Today one common form of drug addiction is the over-use of prescription pain medications. Chronic pain severely affects the quality of life for millions of Canadians, but prescription opioids pose a risk of addiction for those with a legitimate medical need. In addition, patients can develop a tolerance, leading to the need for increasing doses and abuse.
While patients report that cannabis alone doesn't significantly decrease pain, it does make it much more bearable. Medical marijuana also does not have known side effects of heavy opioid use, which, along with addiction, may include nausea, constipation, and depression. Thus medical marijuana used in conjunction with or even in the place of opioids aids pain management with reduced risk of substance abuse.
As long ago as 1931, TIME magazine ran a story describing cannabis' "non-habit forming character" as a viable treatment of opium addiction.
Studies cited as evidence that marijuana is habit forming generally involve very high levels of THC, sometimes in excess of 200 mg daily, or the equivalent of about 20 joints. Suddenly stopping this dosage resulted in patient symptoms such as restlessness, sweating, and disturbed sleep - symptoms which were classified as withdrawal. In studies with lower levels of THC, or where patients were allowed to control their own dosage, there was no spiral toward increased usage and no appearance of "withdrawal"-like symptoms.
In fact, marijuana use among Canadian teens has actually been declining since 2008.
Marijuana vs Alcohol
In fact, a 2009 study found that 40% of alcoholics used cannabis to control cravings, while an additional 25% used it as the primary substitute for alcohol. Alcohol abuse is known to have a damaging effect on brain cells; a 2012 study found that a component of marijuana called cannabidiol (CBD) was helpful in preventing brain damage from excessive alcohol consumption.
Cannabis and hard drugs
Two other major sources of drug abuse in modern culture are amphetamines and cocaine. Both are known as highly addictive and harmful drugs. While some may still insist that marijuana is also addictive, no one seems to argue that it is both less addictive and less damaging than use of amphetamines.
Purists waiting for a magical, cannabis-free cure that dramatically reduces addiction are liable to be waiting a long time for a drug that is both far more expensive, and has more potential side effects than this one treatment we already possess and successfully use.