It probably won’t come as too much of a surprise that consumer spending on prescription drugs has risen over the past decade. Sure, this is partially due to the rise in better and more specialized drugs, but it also appears that, overall, pharmaceutical companies have increased the price.

What might surprise you, though, is exactly how much more we are paying today than we were only ten years ago.  The latest study says that insurance companies are paying through the teeth on the most expensive drugs today, nearly four times as much as they were in 2003.

According to researcher Stacie Dusetzina patient’s out-of-pocket costs for these pricey drugs have also skyrocketed nearly 50 percent, over the same period.  The University of North Carolina-Chapel Hill Eshelman School of Pharmacy assistant professor of pharmacy and public health reports, “This may be a foreshadowing for what’s next. There’s a lot of new, very-high-priced treatments that are getting ready to emerge on the market . which would really increase spending.”

Obviously, this makes drug prices not only a hot topic of debate among consumers, but also within Congress as well.

The lead study author goes on to also warn that this increase in price could make drugs far less accessible to patients. She says, “Patients paying more out-of-pocket tend to stop taking them or be less adherent to the schedule they need to be on. We also know some patients are likely to leave the pharmacy without pickup up their medication because they can’t afford to pay for it,” adding “We’re developing very innovative treatments, but if people can’t access them, that’s a real shame.”

Dusetzina also makes sure to note that drugmakers do not disclose the amounts they give back to payers—give backs like after-the-fact rebates based on monthly medical insurer coverage volume.

Still, Holly Campbell, who is the spokeswoman for the trade group Pharmaceutical Research and Manufacturers of America, comments that those medicines analyzed in the study “include treatments for patients with conditions that previously had few or no options, such as cancer and multiple sclerosis.”

She adds, “Focusing on the list prices of these innovative treatments misrepresents the dynamics of the prescription medicine marketplace by ignoring the discounts and rebates negotiated by insurers and pharmacy benefit managers.”