ALWAS ask your pharmacist, "What is the LEAST amount of money for filling this prescription? The pharmacist may be contractually unable to give a customer the lowest rice UNLESS this question is asked. Then the confidentiality restraint goes away and assuming the pharmacist acts professionally, they MUST offer the lowest price.
Although the GoodRX (or other discount offer may have a lower price one must consider the lower price in terms of meeting a deductible. Often (usually) after meeting the deductible future prices MAY be lower. If (in some cases) a patient will not meet the annual deductible then it is a decision has to be made.