text: Most antidepressants take 6-8 weeks to completely kick in.  Depending on what kind of Wellbutrin you're taking, SR or XL, the time of day does matter.  If you only have to take Wellbutrin SR once a day, take it in the morning.  If you are taking Wellbutrin XL, I would take it in the morning, if it doesn't make you too drowsy.  But I don't think it makes that big of a difference.  \nIf it doesn't work in the next few weeks, go back to your doctor.  Some antidepressants don't work for some people.  There are so many different ones and there may be a medication that works better.