Drugmakers have launched a series of ads in their fight with insurance companies over copay coupons designed to save consumers money at the pharmacy checkout.

Big Pharma and Big Insurance are at it again. This time they’re fighting over copay coupons.

These coupons are provided by pharmaceutical companies to reduce consumers’ costs for brand-name drug purchases.

Some insurers have recently put restrictions on these coupons.

So, the pharmaceutical industry has struck back with a series of ads with slogans like “Why are middlemen trying to keep you from reaching your deductible?” and “You shouldn’t have to fight for your medicine.”

On the surface, copay coupons appear to be good things. They save you money, right?

But what you save at the pharmacy checkout may come back to haunt you later as higher insurance premiums.

To help you understand what’s going on, here’s a breakdown of the two sides of this heavyweight fight.

Copay coupons cover part of consumers’ out-of-pocket costs for brand-name medications. This money comes from the drugmakers.

So instead of paying $65 a month for a brand-name drug, you might pay only $4 a month with a coupon.

Drugmakers promote coupons as a way to help people afford their medications. But the coupons also drive people to buy the companies’ drugs — which helps their bottom line.

Some drugmakers even ask people to share their personal information — including medical data — in exchange for the copay coupon. This helps them know how people are using their products.

While copay coupons lower your out-of-pocket costs, they don’t lower the overall cost of the drug that much.

And insurance companies still have to pick up the rest of the drug’s cost.

Insurers would prefer that enrollees use less expensive generic drugs. It helps them keep their costs down.

To encourage enrollees to choose generics, insurers often set the copay for brand-name drugs much higher than for generics — something like $65 a month versus $10 a month.

“Insurers tier branded drugs to make them much more expensive than the generic, in order to steer consumers to buy the generic. The copay coupons undermine that tiering,” said Matt Schmitt, PhD, an assistant professor of strategy at the University of California at Los Angeles (UCLA) Anderson School of Management.

In response to this, UnitedHealthcare and Express Scripts started a copay accumulator program. This doesn’t allow the part of the copay covered by the drugmaker to count toward a person’s deductible or out-of-pocket maximums.

That means it’ll take longer for a person to reach their deductible. That’s the point at which their better insurance coverage kicks in.

This shift is expected to hit some people especially hard, such as those with a high deductible who are taking expensive medications.

The pharmaceutical industry’s ad campaign strikes out at copay accumulator programs as well as at hospital markups of medications.

High healthcare costs have long been a problem in the United States. But what people pay out of their pocket has increased quite a bit in recent years.

According to the Kaiser Family Foundation, between 2005 and 2015 the average out-of-pocket medical costs for covered workers grew 66 percent. This includes drug costs and other medical care. During that time, wages grew only 31 percent.

For consumers, copay coupons offer immediate financial benefit, especially when there’s no equivalent generic available.

But 62 percent of copay coupons were for brand-name drugs that had a less expensive alternative treatment available, according to a 2013 study in the New England Journal of Medicine.

Lowering a person’s out-of-pocket costs can also help people continue taking their medication regularly, which can reduce healthcare costs from complications.

“A consumer may choose to not fill their prescription that they really need because the copay may be particularly expensive,” said Schmitt. “A copay coupon will lead to them taking the drug they should be taking.”

This is what a 2016 study in Pharmacotherapy found. People using copay coupons for brand-name statin drugs were more likely to stick with their treatment.

Their monthly out-of-pocket costs were also lower than those of people buying statins without a copay coupon.

But total monthly costs — what the consumer and insurance company paid combined — were about the same for both groups. Copay coupons just reduced the consumers’ out-of-pocket spending.

If there’s no cheaper alternative treatment for a brand-name drug, copay coupons can be a good thing for the consumer.

But when there’s an equivalent generic available, “consumers can get access to their medication at a low cost by buying the generic,” said Schmitt. “So it’s really hard to see the argument for a copay coupon in these cases.”

Copay coupons can also drive people to choose more expensive brand-name drugs over equivalent generics. This drives up healthcare spending.

A recent study by Schmitt and his colleagues published in The American Economic Journal: Economic Policy looked at data on drug spending and insurance premiums from 2007 through 2010.

For brand-name drugs that had an equivalent generic available, copay coupons increased the use of brand-name drugs by more than 60 percent and also reduced spending on generics.

The researchers estimated that coupons also resulted in up to $2.7 billion of additional drug spending over a five-year period, just for the 23 drugs they looked at.

In addition, copay coupons let drugmakers raise their prices while keeping the consumers’ out-of-pocket costs the same.

“You’re making the drug relatively inexpensive to consumers,” said Schmitt, “but the full cost is actually not going down by that much.”

When drugmaker Mylan faced criticism for raising the list price of a two-pack of its EpiPen from $100 to $600, it sought to calm consumers by offering some a copay coupon.

When drugmakers can focus on keeping consumers happy, they also have less reason to deal directly with insurers.

Pharmaceutical companies sometimes offer insurers a good price on a drug so the insurer will provide the drug at a lower cost to its members.

That increases sales of the drug. Copay coupons shift that.

“Once you have a copay coupon, you don’t need to offer those price concessions to insurers to achieve low out-of-pocket costs for consumers,” said Schmitt. “You can just do that via a copay coupon.”

But insurers don’t eat the extra costs that come from enrollees choosing brand-name drugs instead of generics. They pass these costs on as higher premiums — which are paid by enrollees and their employers.

So even if you’re saving money at the pharmacy checkout, you might end up paying for it later. And you might not even realize it.

“For consumers, especially those enrollees who aren’t taking the drug and benefitting from the copay coupon, it’s not very transparent to them that their premiums are likely going up as a consequence,” said Schmitt.