Medical credits cards intended to help consumers pay for health care instead may be driving them further into debt, according to a hearing held last week by the Consumer Financial Protection Board.

"This spring, the CFPB published a report on the use of these payment products," said Rohit Chopra, the board's director. "Our research shows that these payment products have less-favorable terms than other general credit products and can land patients with significant amounts of deferred interest. Indeed, over a three-year period, patients paid $1 billion in deferred interest on medical credit cards. This deferred interest isn't something that's fair or transparent — people can find themselves hit with large and unexpected interest costs even when they've been making payments on the bill all along."

The hearing was part of a stepped-up effort by the CFPB, Centers for Medicare & Medicaid Services, Department of Health and Human Services and Department of the Treasury to examine the prevalence and nature of financial products used to pay for health care, as well as their impact on consumers and consumer protections.