in nebistar-h and telmisartan
of telista can cause depression
as side effects. But as you say your depression was there even before the medication was started, I would suggest that you consult your physician to alter the medication to some other medication if possible with no side effects of depression.
If that is not possible, then consult a psychiatrist
who can give you some medication to help with your depression.
If you are already on medication for depression, please ask your psychiatrist if your antidepressant is an old TCA
(Tricyclic antidepressants) type of antidepressants. These are good antidepressants but have lot of cardio-vascular problems and hence are not now a days prescribed with new safer, but yes expensive, anti depressants in the market.
to summarise, your physician and psychiatrist must be able to coordinate their medication such that the treatment of one problem does not increase the other problem.