Drugmakers increased wholesale prices for the 50 top-selling branded drugs by an average of 7.82 percent last year, after increases of 6.73 percent and 6.22 percent in the previous two years, according to Delta Marketing Dynamics. The most recent increase is almost double the overall US economy’s 4.1 percent annual inflation rate last year, The Wall Street Journal reports.

Some individual drugs had double-digit price increases over three years. Glaxo, for instance, raised the price of its Wellbutrin XL antidepressant by 44.5 percent from 2005 to 2007. Sanofi-Aventis boosted the price of its Ambien sleeping pill by 70.1 percent. Shire hiked the price of its Adderall XR ADD drug by 33.5 percent. And Pfizer increased Lipitor’s price by 16 percent.

The Delta Marketing figures represent the wholesale acquisition cost, which is the manufacturers’ list price for a drug, the Journal notes. This doesn’t reflect underlying rebates and discounts given to wholesalers and large purchasers, such as health insurers and pharmacy-benefit managers. While the wholesale list price isn’t what most customers pay, raising it may help boost the starting point for negotiating a final price, the paper adds.

Prices are going up because - drugmakers are trying to keep revenues afloat by raising prices ahead of patent expirations in hopes that patients will switch to newer meds that have market exclusivity, the paper explains. Then there’s the possibility of changing government regulations, which is a theme in the presidential race. Of course, this could backfire and drug prices right up there with the cost of oil when inflation is discussed, because these price hikes inevitably are reflected in co-payments.

“Companies are under great pressure to deliver revenue, and it’s becoming increasingly difficult to do so as generics displace profitable brands,” Bill Little, Delta Marketing’s president, tells the Journal. “I think drug companies, by and large, are in a survival mode.”

Some industry analysts suggest drugmakers are raising prices to protect their margins in case the federal government is given the power to negotiate prices for Medicare Part D -the theory is that negotiations between the industry and government would start at a higher price point, the Journal writes.

Bush administration health officials and industry analysts disagree about whether direct negotiations would lower prices. “Allowing the government to negotiate drug prices would not generate additional savings under Medicare Part D,” Jeff Nelligan, spokesman for the Centers for Medicare and Medicaid Services, tells the paper. “The legislation creating Part D relies on health plans and their related pharmacy-benefit managers to negotiate deep discounts with manufacturers.”

“Direct negotiations clearly could save the feds money, the concept being that the government makes almost 50% of purchases, and accordingly have almost fiat-like power to set their purchase price wherever they wish,” John Ransom, health-care equity analyst at Raymond James & Associates, also tells the Journal. “I’d argue that if the exclusionary clause were lifted, government would be in a position to effectively dictate price.”