I can only speak for myself, but drinking while manic has resulted in exacerbating impulsive / risk taking behavior (drinking more than I normally would, getting in physical fights, antagonizing people around me). When manic I drank mainly to "mellow out" or quell the racing thoughts / high level of alertness and agitation.

When depressed I drank more heavily and more frequently than I did while manic mainly to numb myself and ignore self loathing or suicidal thoughts.

Alcohol has never triggered an episode for me as far as I can tell (but I think it's widely acknowledged that It CAN).