I am really not trying to be rude here. But are you sure the DR is for you if you have to have anti-anxiety and anti-depressant psychoactives regularly?
A lot of medications which require a Rx in NA do not in the DR. This includes antibiotics, hypertension medications, etc.; just about anything except barbituates, heavy-duty pain killers, and erectile dysfunction meds. The latter did not require a Rx before this year either.
It isn't over the counter in the sense that you pick it off the shelf yourself and take it to the cash register. At a Dominican pharmacia, all the medicine is behind the counter, and the pharmacia employee (I doubt if most of them are actual pharmacists) gets it for you.
You don't need a prescription for ED meds either. They just try to limit the sale to Farmacias. But you still see them in some gas stations and Calmados.