"i have taken 200mg bupropion sr (100mg twice a day, eon/sandoz blue pill) for about a month for depression.  (lethargy, fatigue, trouble with focus and memory). and it worked great, i had energy, feel focused and alert etc.  only downside was that after 3 weeks i started having insomnia.  so at my 1 month followup, my doctor switched me to 150mg bupropion xl (1 pill in the morning, global pharm yellow pill.)  i was fine the first morning on the new pill, but by 2pm i couldn&#039;t concentrate and by 6pm i was having headaches and anxiety (both symptoms i haven&#039;t had in the past.)  so i&#039;ll put in my vote for generics are different enough that you might do well on one and poorly on another."