A friend who experimented with GABA told me it made him drowsy for days. I tend to avoid supplements that come close or function as neurotransmitters. For instance when I take tyrosine I feel like I am on speed (and I know that feeling WELL).

I;ve never experimented much with tryptophan but Ray Peat damns it and I can understand why: muscle meat inflames me and as I understand carries a high amount of tryptophan (in addition to methionine)

For me I stick with magnesium, taurine, zinc. B vitamins can get me to sleep (but I seem to wake up soon after). Valerian and chamomile work for me too. I heard kava gives great dreams. I had some animated, like claymation dreams on mugwort.

Lot of sleep options available in supplements. If you do well on GABA good for you.

Read this: http://primalgirl.wordpress.com/2011/11/01/nprimalgirl-sleep-issues-vitamin-d/

Melatonin is certainly useful for inducing sleep, but I and others have found that too much (for me, >1g/night) can cause depression for the next day or two...

It depends on the cause of one's sleep issues. Gaba is a calming neurotransmitter but all the research I've read says it doesn't cross the blood-brain barrier, that's why there's a bunch of things out there that increase gaba levels in other ways. L-theanine (found in green tea) is what has helped me the most, and it's been shown to increase alpha waves in the brain that cause a sense of relaxation and calm. If your problem is too much stress then increasing gaba will definitely be worth trying for sleep. The herb valerian also has a similar affect. Regarding melatonin, I've known people who are energized by it and it keeps them awake instead of puts them to sleep, this could be because most of it goes to the gut instead of the brain, that's just hypothesizing on my part though . . .http://visceralsynergy.com/Visceral_Synergy/About_Dr._Mariotti_files/Melatonin%20Gut.pdf. I also read this, "Healthy young and middle-aged adults usually secrete about 5 to 25 micrograms of melatonin each night - at least 80 times less than is in the commonly sold 2 milligram (mg.) tablet or capsule." So it could be that the dose in the capsules simply is too much for some people depending on how much melatonin your body is already producing. Tryptophan or 5htp is the most effective for sleep for me and many others, and it naturally increases your body's production of melatonin so you don't have to worry about too much melatonin because the body will only make as much as it needs from the precursors. Hormones are probably the most important factor in sleep as they are for all the other physiological processes so it's crucial to focus on doing things that optimize your levels of cortisol, leptin, and insulin, which is what the paleo diet does.

One will find many assertions that GABA does not cross the blood-brain barrier. Some Italian research disputes this, suggesting that at high dosages it does. In addition, the impermeability of the blood-brain barrier to certain substances seems to vary between individuals.

But the blood-brain barrier issue may be moot. The hypothalamus has regions that are not shielded by the blood-brain barrier. In effect, it is the brain's dipstick into the bloodstream. It is sensitive to a vast variety of molecules that cannot otherwise access the brain. It responds to some molecules by stimulating the release of hormones (many from the pituitary, which is attached to the hypothalamus).

Research shows that GABA stimulates the release of HGH. (Once again, some have claimed that this can't be true, as GABA doesn't cross the blood-brain barrier.)

GABA also somehow promotes sleep in most people (possibly by increasing the natural secretion of melatonin. That's only a conjecture, but the hypothalamus is the relay station from the retina to the pineal gland, and is the first responder to changes in light, day length, etc.) As Rogue Nutritionist mentions, anecdotally the dose response is a bit unpredictable, with very high doses making some people less drowsy.

I use GABA sometimes, in oral doses (not sublingual) of up to 3 grams. In high doses it induces something akin to a mild case of the "niacin flush"--tingling skin on face, shoulders, and arms.

Some bodybuilders report that it leaves them short of breath--possibly because of the damping effect on the nervous system. I haven't experienced this, but it is anecdotally widespread. Combined with the flushing, this has sent a few people into a state of high anxiety, contemplating a rush to the ER. Should you choose to supplement with GABA, I'd start with low dosages and see how it affects you.

I makes me quite relaxed and sleepy, and tends to let me get a full night's deep sleep. It doesn't exactly leave me drowsy the next day...but it does leave me a bit, ummm, overrelaxed.

Melatonin + GABA + L-Theanine is killer for sleep promotion. Go sublingual where available.

Not that you mentioned it, but: avoid valerian long-term. Serious liver toxicity.

Especially with daily alcohol consumption.

GABA is very calming and relaxing. I use it in my family daily, always sublingual because it reaches the brain very quickly that way. If sleep is eluding someone due to their tension, GABA would really help. I always take my D in the morning, because I find it to be energizing. I would save melatonin as a later resort, there are other choices (like GABA) that I prefer. Also, I like to start people on less GABA, because taking too much can have an aggravating effect, the opposite of what the proper dose will provide...try starting with 100 mg. sublingually, and add another 100 every half hour until you feel relaxed...you will only ned to do this once, then you'll know your dose.

Melatonin helps me get to sleep, but any dosage more than 1mg gives me side effects ranging from sluggishness the next morning to hallucinations. Seems very strong for a supplement, to me. I take it no more than 1-2x per month, and only when I think I really need it. Given that missing a few hours of sleep is not usually a big deal, I would almost rather just do that than take some wacky brain intruding supplement.