There is no problem taking l-theanine with your other supplements. I take a lot of supplements. Way more than you have mentioned. For sleep, I take a supplement that contains melatonin and l-theanine. Works very well.
Thanks, all. It's kind of weird because 400 mg of l-theanine makes me hallucinate a bit. Feels trippy. But it really mellows me out. Haven't tried them all at one time. Might try it later since they can be used together. Thanks again.
Personally, I've been taking Grape Seed Extract since 1995, no colds, no flus and strong immune system. Allergies and sinus issues are history. THere is so much to say about these OPC's...pycnogenol and grape SEED extract.