I am not actually bipolar, although i was misdiagnosed at a fairly young age, then it was reconsidered later when my doctors noticed that my manias were not as extreme or long lasting as expected. Now i am told that i have severe depression. This affected my schoolwork significantly; there were months where i could not get out of bed, could not concentrate on anything but suicidal thoughts, and saw no reason to bother with my schoolwork because of it. While off of medications, i developed an eating disorder as well, and lost 60 lbs in about 3 months. I couldn't focus on anything, was always depressed, lightheaded, passing out, studying was impossible, and whatever energy i did have i spent at the gym. A lot of the difficulties i faced were solved when i found the right medication. Once i had been diagnosed correctly and found a medication that worked for me, i was able to get myself back in the game. My grades improved, my social life improved, and i decided for sure on medicine. It is definitely still possible to do with depressive disorders, but you need to be on top of your game with treatment and counciling; deciding i was too busy to see the doctor, or that i didn't need the medication, were the things that ruined my success the most.
Right now i have been accepted to medical school and am in a much better place mentally. I still go throuhg depressive episodes, sometimes fairly severe. However i find the further i get on my path, the less often i consider suicide or self mutilation.