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GABA Effects?


Been looking around and do seem to see this anywhere.

Does anyone else get a very rapid heart rate and a huge boost in body temperature after taking around 5 grams of GABA?

Can anyone think of any causes for this since its suppose to be a nervous system relaxant?

  1. It shouldn't, GABAnergic receptors are generally depressive neurons.

  2. FYI, GABA doesn't cross the BBB in any appreciable quantity.

  3. Why in the name of tits are you taking 5 grams at a time?


Yeah... What the hell? Never heard a dose like this. I'd never take this much, so where did you get this idea, OP?


Yeah... What the hell? Never heard a dose like this. I'd never take this much, so where did you get this idea, OP?


Yeah, seems like a lot at one go. I found I got a "hot" tingly skin flush (similar to niacin) at 1g 3x daily and also found it to be good for stress/sleep.


Yes. I bought it as a sleep aid too, and it made me wanna jump out of my skin. Doesn't seem like it crosses the blood/brain barrier either, which would make it worthless as a growth hormone stimulator.

So 2 thumbs down.


as far as dosage goes I was an old Max-OT fan and their general recommendation for GABA was a 3-5 grams 30-45 minutes before bed.


5g isn't too much, but might be overkill. 3g seems to have some positive results with GH

Strength athletes who take 3 g of the supplement GABA quadruple their growth hormone production during and after a training session. Sports scientists at Shenandoah University discovered this when they did an experiment with 11 men (average age 23), all of whom were regular weight trainers.


Got a link to that study? Sounds interesting. I have about 1kg of GABA lying around... if anyone wants any.


I'm going to go ahead call BS. It shouldn't work that way, it would need to reach the brain to illicit a response like endogenous GABA (GH secretion).

I would be more likely to believe the act of training itself spiked the GH, though I don't know about a 4 fold increase, but hormone levels fluctuate throughout the day so it isn't entirely unreasonable.

11 Men is a very small sample, as well. There's no reason to to use more on something that most would consider almost harmless. It leaves the study underpowered, at best.


alright maybe ill try 3-4 g dose next time, i do take 5 g before training too and it actually seems to help me atleast get warmed up feeling.

and @ rsgz I found the link for you on GABA effects on growth hormone around training (if this is the same one?)


When i take about 3g 30-45 minutes before bed, i sometimes get a really "oh my god, my skin is on fire" sort of feeling, and my heart seems to race for a few minutes...but then i relax and sleep great afterwards, but i dont know the cause behind it.


Anyone have any knowledge as to the systemic effects of GABA?

Just because it's primarily neurally active and doesn't cross the BBB doesn't make it worthless, it could act on another area of the body and send signalling compounds to the brain to induce effects vicariously.


Generally depressive.

GABA A receptors are acted on by benzodiazepines, for instance.
GABA B receptors are acted on by GHB.

GABA A receptors increase conductance of Cl into the cell creating a larger negative barrier that must be overcome before threshold is reached and an action potential can be transmitted.

GABA B receptors hyperpolarize the cell by allowing K into the cell, preventing Na channels from opening and conducting the signal.

Most of the effects are primarily CNS related, though there are GABA receptors in the periphery I don't think they're there in any appreciable quantity or that supplementing with GABA would have any measurable effect.


Part of the pituitary gland sits outside the blood brain barrier, so a gaba taken orally may have some influence on it...


When you take a benzo or a z drug growth hormone goes up. I don't think gaba taken orally can pass the BBB


I don't understand why everything I am reading shows that benzos will increase growth hormone, but alchohol will decrease it. One would expect that as a result of their similar effects and mechanism of action that they would have a similar effect on ones hormonal profile.

Can anyone weigh in on this?


taking GABA before bed. christ.


Any comments on the study? I'm reading alot of brotology about what GABA may do but the publish science refutes alot of what's written here


L-theanine is the precursor to GABA and is fucking phenomenal.