Titrated up from 25mcg to 100 mcg over a couple weeks...could definitely feel it, but wasn't a problem, and I didn't have any issues sleeping. Tried 125 mcg once, but started to experience a slight hand shake and went back to 50mcg.
What thethinker said, 100mcgs of real clen would have you shaking like crazy and your heart pounding. If it’s not then something’s wrong with the batch. Just my 2cents.