The cost of brand name drugs commonly prescribed to the elderly rose by an average of 7.4% last year, says the AARP, an increase that greatly exceeded inflation.

The wholesale price of brand name medication to retailers is the largest determining factor in the cost of a particular drug. Prices charged to wholesalers for brand name drugs have been going up since the implementation of the Medicare Drug Benefit in 2006, according to AARP, a lobbying group. Consumers tended not to notice because the new drug benefit meant the government would absorb much of the cost, the group said.

A separate report issued by St. Louis-based pharmacy benefit manager Express Scripts has found that, despite the rise in brand name costs, the increased use of generic drugs has suppressed the overall rise in prescription drug costs. Their report shows that average prescription costs increased by $1.09, compared to a projected $3.58 increase without the “generic effect.”