WASHINGTON — Kathleen Sebelius, the secretary of health and human services, said Thursday that she would provide $25 million more to help states buy life-saving medications for people with H.I.V. or AIDS.

Advocates for patients said the money was not nearly enough to eliminate waiting lists, which have surged to record levels as people have lost health insurance, along with their jobs, and states have cut their budgets.

Ms. Sebelius said she was “reallocating and transferring $25 million in existing resources” to provide medicines for people on waiting lists.

Dr. Howard K. Koh, the assistant secretary of health and human services in charge of the program, said the action “reflects the administration’s commitment to H.I.V. treatment and care.”

In an interview, Dr. Koh repeatedly refused to say where the money had come from.

Ms. Sebelius said she was confident that the $25 million would meet the existing and projected need until the end of the fiscal year on Sept. 30.

As of July 1, about 2,100 people were on waiting lists for the AIDS Drug Assistance Program in 11 states: Florida, Hawaii, Idaho, Iowa, Kentucky, Louisiana, Montana, North Carolina, South Carolina, South Dakota and Utah.

Other states have narrowed eligibility, limited enrollment or restricted the drugs for which they will pay. These measures affect thousands of people.

Carl Schmid, deputy executive director of the AIDS Institute, an advocacy group for patients, said: “The $25 million will help. It’s a start. But it’s definitely not enough.”

Ann Lefert, a policy analyst at the National Alliance of State and Territorial AIDS Directors, said, “We appreciate the action taken by the Obama administration, but we are not sure it will be sufficient.”

Advocacy groups and state officials had urged the administration to provide $126 million in emergency assistance for the current fiscal year, on top of the $835 million that Congress had already appropriated.

The administration’s action follows expressions of deep concern by members of Congress from both parties.

Three Republican senators — Richard M. Burr of North Carolina, Tom Coburn of Oklahoma and Michael B. Enzi of Wyoming — had implored Ms. Sebelius to address what they described as a public health crisis.

John Hart, a spokesman for Mr. Coburn, said, “The secretary is taking a step in the right direction, but it’s not enough to serve the more than 2,000 patients who are on waiting lists.”

Many people with H.I.V. have been able to live long lives, with the use of antiretroviral treatments. But the drugs cost an average of $12,000 a year a person, and many people cannot afford them without public assistance.

“Once patients start taking these drugs, they must continue taking them every day for the rest of their lives,” Mr. Schmid said.

The AIDS Drug Assistance Program serves mainly low-income, uninsured people, many of whom are members of minority groups.

More than 168,000 people received medications through the program last year. About 45 percent of them had incomes below the poverty level ($10,830 for an individual), and all but 2 percent had incomes less than four times the poverty level ($43,320).