Can the bipolar medication help in the manic episodes but not in the depressive ones? which is the course of action in this case?

yes: Many of the traditional "mood stabilizers" are slightly better for preventing mania, (and some, for depressive episodes), but not usually effective for both. Lamotrigene seems to have a particular beneficial effect in depressive states of bipolar disorder; among other agents. Ask your dr if these are an option for you. Best luck.

Options : Regarding medications there are many options to treat the manic phase of bipolar disorder. Fda approved treatments for the depressed phase include lithium, quetiapine and lurasidone. Antidepressants are used but not fda approved and should not be used without anti manic medication.