After working nearly 25 years in retail and about seven years doing in-depth formulary analysis, I've learned one about prescription insurance: copays are confusing. CVS pharmacy hopes to reduce this confusion somewhat by introducing a new "Rx Savings Finder" tool to help pharmacists help their patients find a better deal.

According to a CVS press release this new technology will "enable the company's retail pharmacists for the first time to evaluate quickly and seamlessly individual prescription savings opportunities right at the pharmacy counter."

Not every patient is perplexed by their copay. Some people have a plan where everything is free, or virtually free. For them it doesn't matter whether they are getting a $10,000 drug or a cheap $5 generic.

But many patients both in the commercial and Medicare D market have copays that seem as unpredictable as the stock market. They come to the counter expecting a simple $10 copay and suddenly the cashier is telling them $75. Supposedly, the Rx Savings Finder tool has the capability of accessing the formulary and finding less expensive options.

This all sounds wonderful, I suppose. But as optimistic as I want to be about any innovation that helps patients afford their medication, I have to admit I'm not sure how this will work out.

Here are some of the issues that come to my mind.

1. How accurate will the Rx Savings Finder tool be?

As I mentioned above, I spent seven years doing intensive formulary analysis on virtually every health plan in the country. Formularies change a lot. Preferred status is not always black and white. Copays are not always clear on formulary documents or websites.

I suppose, however, that plans managed by CVS Caremark may have an insider advantage allowing their pharmacies inside information on patient copays.

2. Can the tool identify a clinically appropriate alternative?

What if omeprazole is suggested as a lower copay than pantoprazole? Does that mean we should request a switch even if omeprazole might trigger a drug interaction with another medication in their profile? Of course not.

Ibuprofen may be less expensive than celecoxib, but that switch isn't always clinically appropriate either. My point is that it isn't always just about the price.

3. How much time will it take to check these medications?

If a patient walks up to the counter and is told her copay is $50, will she have to request the Rx Savings Finder service to research a lower cost option? According to a Forbes article, even doctor's offices will have access to a version of this tool that will allow them to "pick lower cost medicines."

My guess is that it will be difficult for this technology to catch on.

4. What if the cheapest medication isn't the best option?

Some will probably see this as simply a strategy to drive patients toward less expensive treatments to ultimately save money for health plans, steering patients away from newer drugs. While this might sometimes be appropriate, there are other times when the more expensive product is chosen because other options have failed or are less safe.

I'm a fan of innovation. And if the CVS Rx Savings Finder turns out to be a market-shifting technology that saves patients thousands of dollars, improves their health, streamlines prescribing and brings about world peace, well, that's great.

But just remember, all that glitters isn't gold. And if something sounds a bit too good to be true, well, you know how that saying goes.