your doctor has a duty of care to give you the right drug, for the right condition, to achieve the right therapeutic outcome. that duty of care includes reevaluating past therapy, and choosing the drug with the best ratio of therapeutic benefits to side effects.
while it might be appropriate in the patients mind taht they receive, for example, Darvocet

their knowledge of medicine is miniscule compared to their health professional, and they should abide by the doctors decision, because frankly the doctor/pharmacist is weighing up aspects of the case that the patient has no concept of, and is acting in their best interest.
the reevaluation of therapy that health professionals do, whilst sometimes off the mark, optimises therapy, and is completely neccessary.
patients who try to tell me how to do my job piss me off. pharmacists dont get a hundred grand a year to count pills and stick stickers on. its a bit more complicated than taht. and while we're at it, if you mofos are ready to wait 1 hour at the doctors surgery, you can bloody well wait a similar amount of time for a pharmacist to double check that the doctor did the right thing.
cheerios