I took 1600mg a day for a week.
It acts as a sedative so might be useful for people with anxiety issues.
It made me slightly depressed though.
Because I cut my L-theanine dose in half while taking it I noticed a cognitive decline. So L-theanine is probably helping to some degree with cognitive issues.
I’m ending the experiment because it’s making me slightly depressed.
I hope this may be useful if anyone else wants to try it.