I read a post similar to this one regarding clen + caffeine and Phate set me straight on the matter. I believe he stated that the two don't target the same receptors and have different mechanisms. Not sure the addition of t3 in the equation would change anything. I don't think the occational cup of coffee or green tea is going to effect things but I wouldn't suggest injesting 200mg of caffeine at one given time. IMO, I would start the t3 and clen without any caffeine at 1st then once you get use to how these compounds effect you then you can add in some caffeine.