I take a number of Rx's and so far have found it impossible, with the ones I take, to find a Part D plan that has all of them in the formulary. So with drugs not on the formulary, I use GoodRX. With all apologies to the 'small town pharmacist' mentioned above, I do find substantial discounts via GoodRX on these drugs. I use national chain pharmacies where my online profile follows me as I travel. I do find that the discount varies from chain to chain, i.e., drug A discount better at chain B and drug B discount better at chain A but all better than the cash price. With my current Part D plan ( Humana/Walmart), one drug is cheaper by 70% using GoodRx over the Part D coverage. So I think there probably is no one correct answer.
If you have numerous scripts that are expensive, it pays to check each one out using your Part D and your discount card at various pharmacies and pick the plan and pharmacy for each drug that best fits. With the proliferation of pharmacies normally within a mile or so radius of each other, multiple stops at multiple pharmacies using the plan that works best for each drug, can save big $. Last week alone, a pharmacy charged a drug to my Part D and, knowing via my GoodRX app, that GoodRX discount was better at the pharmacy, I had them re-ring it up on GoodRX and saved $240 for a one month supply.
And with all due respect to fla-gypsy, GoodRX is in fact free to the consumer and has significant benefit with some purchases. With zero cost to the consumer for this free card, there really is no risk and their app is quick enough to use even while checking out at the pharmacy and it is easy to just show your screen to the pharmacist showing the best discounted price available in whatever town you're in and most times you'll get a price match. If you don't and the difference is large enough, fill the script somewhere else.
On edit: If your drug cost are such that you will go thru the Part D gap and back into Part D coverage, you do need to be aware that monies you pay for drugs using the discount card or cash (in effect Rx's you buy outside of the Part D ins), those monies will not count as far as getting you through the gap and back into coverage. In that event, you need to make advance calculations based on your assumed prescription costs as to whether it benefits you to take the card discounts and not get through the gap or to use a more expensive Part D coverage but get through the gap faster. If using a discount card delays one from clearing the gap or clearing it more slowly, then there is a possibility that the card may be more costly (not due to the fault of the discount card but due to the wording of Part D legislation that doesn't recognize out of pocket expenses not paid through Part D as a qualifying gap payment. Once again, lawmakers and regulators getting in the way of free enterprise.
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