Some people it makes you jittery.I took it lose 50 pounds but weight came back when I quit taking it.Be careful its addictive.It gives u a lot of energy.Rking right about taking early in morning.I took it at 1:00 pm was up all night.Take it about 9:00 am.Best of luck.I finally got approval.Surgery is end of this month.Merry Christmas to me.