synthetic - involving or of the nature of synthesis (combining separate elements to form a coherent whole) as opposed to analysis; limnology is essentially a synthetic science composed of elements...that extend well beyond the limits of biology- P.S.Welch.
L-theanine is most effective in the range of 50-200 mg, with the effect being felt within 30 minutes and lasting for 8-10 hours. Individuals with high stress levels may increase their dosage of L-theanine to at least 100 mg, with no more than 600 mg being taken in a six hour period. FDA recommends a maximum dose of 1200 mg daily, although the reason for this limit is not clear, due to its demonstrated safety. There are no known adverse reactions to L-theanine and no drug interactions have been reported. L-theanine is not affected by food and may be taken anytime, as needed.
L-Theanine at an oral dose of 2,000-8,000mg/kg in rats (human estimated dose of 320-1280mg/kg) cause a dose dependent increase in brain tryptophan and reduction of serotonin, reaching 20.5% and 15.5% at the highest dose.