https://en.wikipedia.org/wiki/Theanine#Pharmacodynamics
Did it improve your POIS symptoms as well or only the PE part?
Do I feel tired and fatigued after orgasm with l theanine? No i feel normal. But I need more time to assess if its preventing pois because I slept 5 hours today and 6 yesterday, with l theanine I feel less tired. Other variables, I have not been eating enough protein a day all week so I need to get back on a normal 8 hour sleep schedule and good diet before I can see if there is a direct link between reduced pois under l theanine. But its certainly preventing my premature ejaculation by 40minutes or above.