20 mg of prozac is one of the lowest dosages. Personally I would try the increase - there aren't many side effects with prozac so it should be safe. I myself am on 80 mg per day as part of my daily cocktail of meds. I've tried so many of the antidepressants but ended up back on prozac and am glad. I had so many bad reactions to the newer meds that are out. I'm staying with the tried and true.