Federal officials said yesterday that problems in the new Medicare prescription drug program should not keep patients from promptly getting their medicine.

"Our message is, 'Don't leave the pharmacy without your drugs,' " Health and Human Services Secretary Michael Leavitt said in a conference call with reporters, noting that enrollment in the program has surged in recent weeks.

But pharmacists and consumer advocates said glitches remain in processing claims that can take an hour or more to solve.

About 10 percent of cases involving the new drug benefit have problems that cannot be fixed in a few minutes, said Diane Silverman, a pharmacist for The Medicine Shoppe in Penn Hills.

Rudy Medved, owner of Medved's Pharmacy in Charleroi, put the number at about 20 percent.

"You could be waiting two hours to get a problem resolved," Mr. Medved said.

While fewer problems are being reported, some consumers are still not getting their medications, said Fran Chervenak, managing attorney for the Pittsburgh office of the Pennsylvania Health Law Project.

Federal officials said they were taking steps to improve the system, including a toll-free phone number for pharmacists and more operators to answer their calls.

But those efforts do not always help, pharmacists said.

Pharmacies often have to contact private plans that administer the drug benefit to resolve problems, which can be "a clerical nightmare," Ms. Silverman said.

She often tries to dispense medications and iron out problems with the plans later. But that is not always possible, particularly with more expensive medications, she said.

Health plans say they're doing what they can. In some cases, that means working with the government to correct electronic files regarding individuals' coverage. Insurance companies say they are prioritizing calls from pharmacists so that urgent matters are handled first.

"If you were calling us during the first week, ours and every call center in the country would tell you we were buried," said Terry Seligman, vice president of pharmacy at the UPMC Health Plan. "But now, pharmacists are getting through on a regular basis."

Pat Epple, executive director of the Pennsylvania Pharmacists Association, recommended that patients go to the pharmacy a day or two before their prescriptions run out to get a refill. That way, they can simply come back the next day for drugs rather than wait in the store while pharmacists handle the red tape.

Last week, Pennsylvania joined other states in announcing backup plans to ensure that Medicaid recipients who also receive Medicare get their medications. More than 20 states have stepped in to help.

Pennsylvania has agreed to cover higher copays and at least five days of medicine for those recipients if they have trouble getting their prescriptions filled.

The state program, which is being publicized through pharmacy associations, consumer groups and two state government Web sites, was used by pharmacists to fill 100 emergency prescriptions yesterday.

But that doesn't mean things will be easy at the pharmacy counter, Ms. Epple said. Pharmacists still can spend up to two or three hours on a single case, she said.

States also could face challenges in getting reimbursed by the drug plans. Federal officials have said they can't directly reimburse states for their backup pharmacy systems because Medicare has already paid health plans to provide the medications.

Federal officials said yesterday that they have been in touch with states about the matter.

"States can work with us and we will facilitate reimbursement," said Dr. Mark McClellan, administrator of the Centers for Medicare and Medicaid Services.

After a conference call yesterday with the federal government, Pennsylvania officials said they've received assurances that Medicare will help them collect from the health plans.

"We're confident that we will be reimbursed," said Stacey Ward, spokeswoman for the Department of Public Welfare.

Despite problems with the new program, which began Jan. 1, more and more Medicare recipients are signing up.

Since Dec. 13, 2.6 million people have signed up for so-called standalone plans that provide drug coverage under the new program, federal officials said yesterday. That's up from about 1 million people who had signed up from mid-November to mid-December.

About 4.5 million people have been enrolled in Medicare managed care plans that provide both drug and medical coverage, up from 4.4 million on Dec. 13. And about 6.4 million retirees are enrolled in private plans that receive subsidies from the new program, compared to 5.9 million a month ago. Many of those people, however, already had some prescription drug coverage. And Medicare recipients who also receive Medicaid had no choice but to join.

"The good news is more people signed up," said Robert Hayes, president of the Medicare Rights Center. But he noted that more than 18 million Medicare recipients are eligible but have not enrolled.

"There remains a huge gap between people who need help paying for medicine and this program's ability to help."