I looked for side effects because I developed calf and thigh pain...

I looked for side effects because I developed calf and thigh pain when I tried to start running again. Bingo! I see I am not alone. This is a very deviliating side effect (I had to walk home; couldn't run). Also, my heart rate is much higher than usual for the same level of activity (I see, this, also has been reported. ALSO, I couldn't sleep much of the night (again, similar reports). Other than that, a remarkable drug (I was taking 500 mg up until searching on Google today). These are not "trivial" side effects.