WASHINGTON — At a time when low-cost generic drugs are being embraced as one of the few ways to slow skyrocketing health costs, the Food and Drug Administration has a backlog of more than 800 applications to bring new generic products to the market — an all-time high.

As a result, experts say, consumers will have fewer generic drugs available in the years ahead than the industry is ready and able to provide. The FDA, however, has told Congress that the office that reviews new generics needs no additional money, and the agency has no plans to hire more reviewers.

"We are very aware that many, many people are waiting for more generics to be approved and that there is frustration about the backlog," said Gary Buehler, director of the agency's Office of Generic Drugs.

He said he expected a record number of applications in 2006 — and an even larger backlog — because "we don't believe we'll be getting any staff increases in 2006." Buehler said his office received an all-time monthly high of 129 applications in December alone.

The Bush administration has strongly advocated generics as a way to hold down health-care costs, and Centers for Medicare and Medicaid Services Director Mark McClellan said in an interview this week that an ever-expanding number of generics is essential to controlling the cost to the government and seniors of the new Medicare prescription drug program. In a recent federal report on health-care costs, about the only bright spot was a slowdown in the rate of prescription drug spending that was credited largely to growing use of generics — which now account for more than half of all prescriptions.

"This huge backlog of generic applications is just unacceptable," said Rep. Henry Waxman, D-Calif., one of the sponsors of the law that made generics more easily available two decades ago. "This is the time for the FDA to be ramping up its generic reviews, not to be falling so badly behind."

Last year, the generics office took an average 20.5 months to review each application — compared with 19.9 months in 1999 — although by statute the agency is obliged to do the job within 6 months. The FDA's Buehler said the agency gives priority to "first generic" applications for drugs just losing patent protection, but documents show the backlog for all generics is now double what it was just three years ago.

Although the office approved more than 450 applications last year — 23 fewer than the year before — it fell further behind.