16 March 2012

The dangers of doping

Dagga has hit the news with Cape Cobras' Rory Kleinveldt expected to plead guilty to doping charges. There's no denying the weed's popularity, but did you know it could be deadly?


Dagga has hit the news again with Cape Cobras' seam bowler Rory Kleinveldt expected to plead guilty to doping charges.

According to the SA Cricketers' Association (Saca) traces of cannabis were found in the player's test sample after an anti-doping test conducted in February. Kleinveldt was handed a provisional suspension, Saca said, pending a formal anti-doping enquiry.  

Smoke it, brew it or eat it – there's no denying the popularity of the weed known by as many names as there are ways to use it. There's also no denying its addictive properties and the well-known dangers that accompany the use of it, but did you know it could be deadly? Or that it could literally shrink your brain?

New research says it can; and while many still tout the drug as an effective painkiller that subdues the agony of certain illnesses, there is substantial research being done which debunks not only this theory, but proves that the use of dagga may actually not have any positive benefits at all.

Dagga shrinks the brain

One study conducted by the Orygen Research Centre and the University of Melbourne, has shown that long-term heavy use of marijuana may cause two important brain structures to shrink. Brain scans showed the hippocampus and amygdala were smaller in men who were heavy marijuana users compared to non-users, the researchers said.

The hippocampus regulates memory and emotion, while the amygdala plays a critical role in fear and aggression.

The study also found the heavy cannabis users scored much lower than non-users in a verbal learning task, which involved trying to recall a list of 15 words.

Yet pro-dope groups supporting legal sales and regulation of marijuana took issue with the findings, particularly because the study subjects were men who were heavy, long-term users. They claimed that the study might have delivered different results were the subjects "moderate or occasional users".

Quitting dagga as hard as cigarettes

Adding fuel to this raging debate is another study at the Johns Hopkins University School of Medicine in Baltimore, which has shown that quitting marijuana can cause withdrawal symptoms as severe as those from quitting tobacco. This would then imply that the addictive nature of the drug would eventually lead to the aforementioned "moderate or occasional users" becoming addicted and finding it harder to cease using.

The study found that as with nicotine withdrawal, quitting marijuana caused symptoms such as irritability, anxiety, sleep problems and difficulty concentrating.

Thus, as lead researcher Dr Ryan Vandrey concluded, "Marijuana is not as innocuous as some people would lead you to believe."

Depressed teens vulnerable to dagga

This is one of the primary concerns many have with teenagers and their attraction to the weed – especially depressed teenagers who, according to a report from the White House in the US, are most vulnerable.

According to a White House Office of National Drug Control Policy report , teens who reported being depressed at some point in the past year were more than twice as likely (25%) to have used marijuana than those who weren't depressed (12%).

Even more shockingly, it revealed that marijuana use by teens not only increased their risk of developing a mental disorder by 40%, but that teens who used marijuana at least once a month for a year were three times more likely to have suicidal thoughts than those who didn't use the drug.

Turning it into a vicious cycle, the paper also noted that teens who smoked dagga when they felt depressed were more than twice as likely as other teens to abuse or become addicted to it.

Dope deadly after heart attack

However, as we all know, it is not only teenagers who abuse this easy-to-come-by drug. Adults are just as guilty – and perhaps even more at risk of the dangers associated with it.

A US study of the Baby-Boomer generation who were long-time marijuana users found that the number of 45- to 64-year-olds who reported marijuana use was three times higher than it had been 10 years earlier. However the crux of this study, carried out at the Beth Israel Deaconess Medical Centre in Boston, was to determine whether these ageing marijuana users would have a poorer prognosis in the years following a heart attack.

Their findings were grim: among more than 1 900 heart attack patients the researchers followed, those who reported regularly smoking marijuana in the year before the attack were two to four times more likely to die within the next four years.

The researchers claimed that this could be because marijuana has a number of effects that could be dangerous for older adults, with risk factors for a heart attack. Since the drug triggers a spike in resting heart rate, as well an increase in blood pressure it speeds the heart rate which creates a greater demand for oxygen, and can also limit the body's ability to use oxygen.

Their findings highlighted the fact that marijuana users had higher odds of dying from both cardiovascular causes and causes unrelated to their hearts. These elevated risks remained even when they factored in the effects of cigarette smoking, a habit common among marijuana users.

Dagga not effective painkiller

And for those who still believe that dagga used for "medicinal purposes" such as a painkiller is effective – think again. Not only is it ineffective, but it may actually exacerbate a number of other problems.

The Austrian study conducted at the Medical University of Vienna, found that oral cannabis (a form of medical marijuana) was ineffective in treating certain types of acute pain and actually increased sensitivity to some other kinds of discomfort.

The researchers admitted they were surprised to find an absence of any form of analgesic activity of THC-standardised cannabis extract during their study and instead found that high doses of cannabinoids may even caused increased sensitivity in certain pain conditions.

This is contrary to previous research which implied that cannabis and tetrahydrocannabinol (THC - the main psychoactive component of marijuana) may help ease chronic pain in cancer patients, spinal cord injury patients, and people with multiple sclerosis. Yet the researchers stand by their findings and described them as "conclusive".

Sources: HealthDay News, Reuters Health,

(Amy Henderson,, updated March 2012)

(Photo of cannabis/dagga from Shutterstock)

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