Right: no laughing matter. Marijuana smoking has often been a feature of comedy films, such as the Cheech and Chong series. However, driving while under the influence of cannabis is now known to be a major cause of traffic fatalities in America. '

Found a word you're not familiar with? Double-click that word to bring up a dictionary reference to it. The dictionary page includes an audio sound file with which to actually hear the word said.

Arguments against marijuana being made legally available for medical purposes

1. There are many health risks associated with the use of marijuana for medical purposes
Taking marijuana has been associated with a number of health risks.
Although smoking marijuana does not have the same degree of risk as smoking tobacco (because of the frequency of usage), smoking anything over long periods of time does add to risks of contracting forms of cancer of the respiratory tract. Studies have suggested that smoking marijuana increases the risk of both oral cancers and lung cancer.
Some studies have suggested that marijuana might be a trigger for adverse cardiovascular events, including tachyarrhythmias, acute coronary syndrome, and vascular complications, especially in older users, and may be a risk factor in congenital heart defects for their children. It has also been implicated as a possible precursor of strokes. Ischemic stroke is found almost exclusively in people of advanced age. However a number of reports have shown an association between cannabis abuse and ischemic stroke in young people.
Marijuana users generally have poorer oral health than non-users, with an increased risk of dental caries (cavities) and periodontal diseases, along with dysplastic changes and pre-malignant lesions within the oral mucosa. In addition, users are prone to oral infections, possibly due to immunosuppressive effects.

2. Medical marijuana use would expose patients to increased road accident risks
Marijuana has been shown to have a number of adverse effects on drivers.
Laboratory studies examining the effects of marijuana (cannabis) on skills utilised while driving detected impairments in tracking, attention, reaction time, short-term memory, hand-eye coordination, vigilance, time and distance perception, decision making, and concentration. More recent controlled laboratory research has suggested similarly that cannabis impairs tasks of selective and divided attention, time estimation, and executive function.
Marijuana is the second most common drug (found in about 15% of fatalities in Victoria), followed by the amphetamine-type stimulants (4%) and opioids (4%). Illicit drugs are present in almost 20% of drivers killed in Victoria. A survey of almost 500 injured drivers admitted to a major road trauma hospital found that cannabis products were present in 46%, opioid analgesics in 11% and amphetamines in 4%.3
It is recognised that a number of prescribed medications are already contributing to increased road accident rates. Critics of the medical use of marijuana claim that such use would only make the existing problem worse.

3. Medical marijuana may increase anxiety and depression
One of the main arguments against the medical use of marijuana is that it does not produce Serotonin, but affects anandamide which is present in brain and produces soothing feeling by reacting with THC which is present in marijuana.
This can actually increase depression and cause schizophrenia which has been noted a side-effect regular, prolonged illegal use.
Opponents of the medical use of marijuana note that while it is always safer to administer antidepressant under medical care than use the illegal substance. The constituents of marijuana interfere with the process of balancing the chemicals which antidepressants work to achieve and so may aggravate the condition instead of curing it.
On October 13, 2011, Science Daily reported 'Although cannabis may cause an immediate euphoric feeling, for a large group in the population its use can lead to an increase of depressive symptoms in the longer term.'
In a report published in the British Medical Journal in November, 2002, it was noted that an Australian study of 1,600 14- and 15-year-olds found that the young women who had used marijuana weekly as teenagers were twice as likely to have depression as a young adult than women who did not use the drug. Daily use as a teenager was associated with four times the risk of depression for young women.
It has also been claimed that long-term marijuana use leads to structural changes in the brain that can cause serious mental problems. One study showed hippocampal volume in cannabis users was inversely correlated with cumulative exposure to the drug in the left hemisphere-a finding that suggests 'the left hippocampus may be particularly vulnerable to the effects of cannabis exposure and may be more closely related to the emergence of psychotic symptoms.'

4. Supporters of marijuana decriminalisation are exploiting the medical marijuana argument
It has been claimed that many of those promoting the legal use of marijuana are merely trying to shift community attitudes as a way of having recreational use decriminalised.
In 1979, Keith Stroup, the director of the Unites States National Organization for the Reform of Marijuana Laws (NORML), told an audience at Emory University that NORML would be using medical marijuana as a 'red herring to give marijuana a good name.' Stroup explained the strategy when he said, 'We are trying to get marijuana reclassified medically.'
Kevin Zeese of the United States Drug Policy Foundation was quoted on several occasions as saying, 'Medical marijuana is the first step to decriminalization.' Eric Sterling of the Criminal Justice Foundation has further said, 'Medical use of marijuana is an integral part of the strategy to legalize.'
It has been claimed that supporters of the decriminalisation of marijuana are using public sympathy for those suffering terminal diseases as a means of shifting popular perceptions in favour of marijuana.

5. Medical marijuana use would promote wider use of marijuana within the community
It has been argued that the legalisation of marijuana use for medical purposes will serve to normalise the use of the drug and thus encourage its use within the wider community.
Dr Yu-Wei Chu of Michigan State University's 2012 study on the apparent effects of legalising the use of marijuana for medical purposes supports this claim. Dr Yu-Wei Chu has stated, 'My results indicate a 10-20% increase in marijuana arrests and treatments after the passage of medical marijuana laws...A 10-20% changes in marijuana and heroin use represent large legalization effects.'
It has further been noted that recreational use of marijuana is likely to increase after the drug has been legalised for medical purposes because patient share their supply with friends and family members.
Research has shown that medical marijuana diversion is a significant problem among adolescents in Colorado, which has had legal use of marijuana for medical purposes since November 2000. A study of teenagers being treated for substance abuse, found that nearly 75% of participants reported using another person's medical marijuana a median of 50 times. In addition, use of marijuana was perceived by most adolescents as having 'slight or no risk'.
A report prepared by Family Voice Australia for the New South Wales parliamentary committee investigating the medicalization of marijuana noted, 'Legalising marijuana for medical use combines the risks of increasing availability and normalising of drug- taking behaviour, leading to a greater frequency of marijuana-taking at an earlier age, increased abuse and dependency, and more 'conduct disorder' symptoms among adolescents.'