SAN FRANCISCO -- It's a phrase people are loath to hear when they're looking for a new primary-care doctor: Not accepting new patients.

Some parts of the country already lack an ample supply of general internists, pediatricians and family physicians, forcing patients to drive further or wait longer for care. If a comprehensive health reform bill passes and extends coverage to millions of uninsured Americans, many are asking if there will be enough primary-care doctors to handle the increased demand for medical services.

``I think we'll see some effect like Massachusetts did, but I'm not expecting there will be chaos,'' said Lori Heim, president of the American Academy of Family Physicians and a family physician at Scotland Memorial Hospital in Laurinburg, N.C.

Heim was referring to the statewide health-insurance overhaul Massachusetts began phasing in in 2006, which provides a test-case example. It succeeded in lowering the state's uninsured rate to 2.7 percent, by far the lowest in the nation, but also exacerbated problems in areas that already had primary-care shortages.

``It's not that it gets worse; it gets more noticeable,'' said Brian Rosman, research director for Health Care For All, a Boston-based advocacy group that is tracking the overhaul's effects. ``What it did do is spur state authorities to pay attention to this issue.''

STATE EFFORT

Two years ago, Massachusetts authorized retail clinics for the first time, allowing drugstore chains to pick up some of the slack by offering consumers a place to go to for routine care such as immunizations and ear-infection treatment, he said. The state also started a loan forgiveness program to help offset the debt burden for new medical school graduates who agree to serve as primary-care doctors in underserved areas.

``They're working at addressing it as best they can, but the long-term solution has to come from the federal government and has to involve building payment structures that support'' primary care, Rosman said.

Dr. Louis Sullivan agreed. Sullivan, former secretary of Health and Human Services in the George H.W. Bush administration and president emeritus of Morehouse School of Medicine, called for more federal leadership on the issue during a recent Webcast discussion at the Kaiser Family Foundation.

``We have in the United States a relatively unrecognized shortage of health professionals, and it really is going to get worse if we don't do something about it,'' he said, speaking of nurses and pharmacists as well.

``Between 1956 and 1981, we had a massive increase in training programs for doctors and other health professionals,'' he said. ``States did play a role, but HHS provided leadership and funding. That kind of vigorous federal leadership is missing today.''

Sullivan suggested that greater use of physician assistants and nurse practitioners could help alleviate a primary-care crunch, an idea that remains controversial.

``We do need to help redefine the scope of practice in all kinds of health professions because physicians don't have to do everything,'' he said. ``There are many things that other health professionals with less training can do just as well.''

In many ways, primary-care physicians, or PCPs, are on the front lines of medicine, providing preventive and first-stop care for many common and chronic ailments and making referrals to subspecialists when necessary.