Minor stomach issues (very minor), jaw clenching, added anxiety, and fatigue. Which I do still feel quite a bit, but I have definitely benefited from going to 20 and I'm sure the fatigue will pass with time. When people think of side effects, they immediately think about those that came when they first started. The side effects that came with dose increases were nowhere near as bad. Of course you always hear that everyone reacts differently to it, but if you were able to get past side effects once, I believe you will be able to do it again.