Hello there, well, Lamotrigine and depakote are not antidepressants, they are mood stabilizers. You have not given me vital details like your brother s age, onset of the illness, how many episodes he has had and what were the episodes (depression/ mania/ mixed)? and for how laong has been on medications and the dosage he is on?From your question, at present I presume that he is depressed , none of the medications that he is taking right now are antidepressants. Lamotrigine is a mood stabilizer which works well for bipolar depression. In addition to these drugs I has to been on antidepressants also for a while. If you could give me more details, I will be in a position to help you better. My advise is to see a Psychiatrist at the earliest.