WASHINGTON — The Social Security Administration is straining from spending cuts and extra work brought on by the new prescription drug benefit, according to internal correspondence from an agency official.

The agency is helping senior citizens and the disabled enroll in the drug benefit, plus it has responsibility for determining who qualifies for extra government help in paying for medicine. The agency is seeing a huge increase in phone calls and office visits as a result.

One out of three calls to the agency's 1-800 number for information results in a busy signal, and people are visiting Social Security Administration offices at a rate of nearly 200,000 per day, said an e-mail to employees from Linda McMahon, deputy commissioner of operations for Social Security.

"Ever since the Medicare Modernization Act passed, those of you on the front line have been expressing your deep concern that SSA is not positioned well to help people understand, enroll in and negotiate the new Medicare Part D coverage," McMahon said. "Now we are seeing the consequences of that fact."

Rep. Henry Waxman, D-Calif., obtained the e-mail and sent it to House Speaker Dennis Hastert, R-Ill. The Social Security Administration confirmed that the e-mail was legitimate.

Waxman told Hastert that the agency is considering closing offices for certain periods to allow staff to complete other work. He asked that the appropriate congressional committees investigate.

In her Jan. 21 e-mail, McMahon told employees that Congress had passed the agency's budget in late December, delivering $300 million less than President Bush had requested. The agency's budget is $9.1 billion for this fiscal year — a cut of almost $200 million. The budget covers administrative costs, not payments to seniors and the disabled.

To cope, McMahon said, the agency would do fewer reviews of whether disabled adults and children should continue getting monthly cash payments called Supplemental Security Income. It would also look at nonpersonnel spending to free up more money for overtime.

The reviews of SSI recipients are important because they can prevent people from getting payments even after they've fully recovered from illness or injury. The Government Accountability Office has stated that the reviews return $11 to the treasury for every $1 that is spent conducting them.

If the information in the e-mail is correct, it's a grave concern because 50 million people get benefits through Social Security, Waxman said.

"While these benefits are not at risk, the ability of the Social Security Administration to manage the program, respond to beneficiaries' basic inquiries and questions, and prevent fraud and abuse appears to be severely degraded," he said.