Lower dosages 100-500mg or so at a time seems to raise gaba levels and lower stress. Dosages above that seem to have a stimulating effect releasing more dopamine. You kind of have to figure out what dosages work for you. Start out low. I would use 100mg. Try that up to 3x a day every 3-4 hours. If you notice nothing bump up to 200mg and so on. I've felt the effects of both the low and the highs of theanine. Low dosage is subtle but relaxing. I notice alert yet relaxed feeling. High dosages close to 1,000mg I noticed a strong dopamine buzz. It was more stimulating. Increased confidence and more aggressive actually.