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By Nancy Schimelpfening, About.com Guide to Depression since 1998

Study Says Marijuana Has Antidepressant Effect, but Only at Low Doses

Tuesday October 30, 2007

A new study published in the October 24 issue of The Journal of Neuroscience says marijuana exhibits an antidepressant effect, but only at low doses. At higher doses, the opposite effect was observed, with serotonin levels dropping off even lower than the control group.

Dr. Gabriella Gobbi and colleagues, of McGill University and Le Centre de Recherche Fernand Seguin of Hôpital Louis-H. Lafontaine, injected rats with a synthetic cannabinoid and then subjected them to the Forced Swim Test, a test used to measure depression in animals. At the low dose, the cannabinoids produced an antidepressant effect in the rats accompanied by increased activity in the neurons that produce serotonin. Increasing the dose beyond a set point, however, reversed the effect and serotonin levels dropped, becoming even lower than the control animals that did not receive the drug.

Because of the difficulty in controlling the dose when marijuana is smoked, the authors say there are problems with using it directly as an antidepressant. "Excessive cannabis use in people with depression poses high risk of psychosis," said Dr. Gobbi in a press release. Instead, she and her team are focusing their research on a new class of drugs which would enhance the effects of the brain's natural endo-cannabinoids.

Comments

October 30, 2007 at 8:56 pm
(1) T says:

Just because an animal on a high dose of marijuana is immobile for a longer period of time than a sober one that does not mean it is depressed, it means it is stoned and humans alike don’t move around a lot when stoned.
But I concur that using cannabis against depression is not a good idea. I went into an episode of psychosis after using cannabis excessively while unemployed, broke and blue.
I thought that it was excessive levels of seratonin that produce psychosis, at least that’s what the medication I got at the time was suposed to block. How does that fit in with the study finding a drop in seratonin levels of those animals that took high doses?

October 30, 2007 at 9:13 pm
(2) T says:

Oh, and I was searching for some tips to naturally alliviate depression, got any of those? I know there is food, exercise and meditation but what about the specifics. What type of foods? What kind of exercise, long distance running or weightlifting? What type of meditation, is breathing exercises enough or should one delve into focusing on the third eye or practice tantra in solitude?

October 31, 2007 at 9:46 pm
(3) Willow says:

I smoke pot on a somewhat daily basis. Not quite everyday, but at least 4x wk, and only in the evening. It really does and did lift any kind of depression I might have had. It makes me feel happy, yet I’m not hysterically laughing, like some people whom smoke it can get. I just like the taste and the end result.

March 1, 2009 at 9:45 pm
(4) spasmelodic says:

Is synthetic cannabinoid available in suppository form ?

July 20, 2009 at 11:02 pm
(5) Krispy Kreme says:

Not sure if this phenomena is directly related to your serotonin level, but the intensifying of experience ganja engenders works against you if your thoughts stray to a bad place.

September 29, 2009 at 9:46 pm
(6) Sharkasm says:

I’ve suffered from depression for many years and was only diagnosed a couple of years ago. For me, pot has worked better than any anti-depressants i’ve been prescribed, and as the swim test would indicate, it worked great on low doses, just a puff here and there throughout the day, but higher levels just made me tired and well.. stoned. It became a joke with my brother who lives with me, because he could tell if i had been smoking because of the ambition I had. In another country I would advocate it as an anti-depressant when used properly, but because of the legality of it, I cannot.

So here’s my dilemma. Prescribed anti-depressants have done next to nothing, except help me handle anxiety attacks, which were at times severe. I can’t smoke pot anymore because of my job and random testing. Within weeks of quitting I started noticing all of the classic symptoms returning fast and furious. I’m not sad or bummed out all the time as most are because of the way i am vigilantly optimistic, but i just cant find the ambition that i need to get through most days.

Here’s the question I pose to you. What anti-depressants are most likely to give me the same results as a low level of marijuana?

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