Marijuana Alleviates Depression in Small Doses, But Too Much Pot Could Do Opposite

Smoking a joint might act as an anti-depressant, but smoking five joints could be harmful. A McGill University study has found small doses of marijuana can raise serotonin levels, while too much of the plant can drop serotonin levels dramatically. Digital Journal — Scientists at Montreal’s McGill University discovered that low levels of THC, the active ingredient in marijuana, increases serotonin levels in lab rats. Depression sufferers are found to have low levels of serotonin, the neurotransmitter that floods the brain with feeling of happiness and satisfaction. The press release goes into further detail about the study’s conclusion:

The anti-depressant and intoxicating effects of cannabis are due to its chemical similarity to natural substances in the brain known as ‘endo-cannabinoids,’ which are released under conditions of high stress or pain… . This study demonstrates for the first time that these receptors have a direct effect on the cells producing serotonin.

But don’t substitute a spliff for Prozac just yet. Lead researcher Dr. Gabriella Gobbi found that high doses of THC can worsen the effects of depression and other psychological ailments. She explains:

Low doses had a potent anti-depressant effect, but when we increased the dose, the serotonin in the rats' brains actually dropped below the level of those in the control group. So we actually demonstrated a double effect: At low doses it increases serotonin, but at higher doses the effect is devastating, completely reversed.

The McGill researchers are concerned that marijuana smokers may not be able to judge their dosage amounts properly. They claim that smoking joints doesn’t offer the best quantitative measure of marijuana dosage. Instead, Dr. Gobbi and her colleagues are focusing their research on a new type of drug which enhances the effects of the brain’s natural endo-cannabinoids.