Are actors able to perform while using Prozak?

Yes, I was on one of those (I can’t remember which), and I was still able to act.

For the method actors it might get difficult to perform.

It depends on how the medication affects you. Some people may not have certain emotions cut off.

A good bit of acting is pretending to have those emotions. I agree with @rebbel as well.

I agree with @tranquilsea It depends entirely upon the person and how they react to the medication.

I think it depends how the person is affected. There is a wide range of various effects an antidepressant drug can have. I think the person who feels like a “zombie” while on an antidepressant would probably have trouble acting, but the person who feels the antidepressant simply lifted him out of an emotional sinkhole would have no problem (and might even find it easier to act).