Will Smoking Medical Marijuana Kill Brain Cells?

Marijuana is the most commonly abused illicit substance in the US, with 26 million Americans smoking pot at least once in 2008. Sixteen states now have legal medical marijuana programs as well.

Forty years ago, there were reports claiming that brain damage was caused by smoking marijuana. There were descriptions of marijuana smokers as lazy, apathetic, dull, delusional, irrational, and unproductive, which then gave reason for people to assume smoking marijuana resulted in brain damage.

As modern brain imaging was invented, such as CAT scans, no evidence of brain damage was seen in heavy chronic marijuana smokers. At Tulane Medical School in the 1970′s, animal studies were accomplished looking at massive doses of THC. Massive in these studies was 100 times the psychoactive doses in humans. The first set of studies showed significant EEG brain changes with implanted electrodes in monkeys. These changes, however, switched back to normal within one hour of drug administration.

Further testing with the monkeys was fairly inconclusive, however, on autopsy there appeared to be some damage to the brain’s hippocampus. This is a region associated with intellectual function in humans. So the assumption was that humans smoking marijuana ended up with brain damage.

Some years after the Tulane results, the National Center for Toxicological Research repeated the Tulane study with significantly more animals. There were 4 groups containing sixty five monkeys: 1) High dose THC inhaling 2) Low dose THC inhaling 3) Placebo 4) No inhalation at all. No brain abnormalities were seen in any of the groups.

Based on previous scientific evidence, marijuana induced brain damage could not really be proven. That could be changing. There was a new study in late 2010 that showed potential for marijuana smoking to lower cognitive function.

In a paper presented meeting of the Society for Neuroscience, Dr. Staci Gruber, reported that in a small study of participants who began smoking pot before 16 years of age, they performed significantly worse on cognitive function tests than both non-smokers and those who became chronic smokers later in life.

This will necessitate a larger study, as there could be potential for longer term vulnerability with starting smoking while the nervous system in still immature.

Want to find out more about medical marijuana Arizona , then visit Arizona MMC’s site on how to obtain your Arizona medical marijuana card from one of our qualified doctors.