"i was prescribed tenuate extended-release tabs because of my caffeine sensitivity.  of course, i noticed a change but not the jittery/shaky feeling that comes with harsh stimulants.  my side effects included nausea, constipation, blurred vision (which i didn&#039;t associate to the meds). i lost 15 pounds over a three month period including the winter holiday period but noticed after that i was not losing anymore.  two months later and a 6 lb weight gain, i&#039;ve decided to stop taking the meds.  immediately, i noticed extreme exhaustion and an inability to get going."