Lots of medical problems need prompt attention—probably sooner than you can get an appointment with a physician—but aren’t serious enough to need a visit to a hospital emergency room.

For nonemergencies, there’s a third option: urgent-care centers. Most of these are open seven days a week, take patients on a walk-in basis, and treat minor ailments such as ear infections, strep throat, lacerations, even some fractures.

The level of treatment varies at the more than 50 urgent-care centers in the Washington area. At Medics USA Medical Center near DC’s Dupont Circle, walk-in patients generally see a physician’s assistant, while those with appointments see a doctor. At CVS’s MinuteClinic, with ten area locations,  patients are diagnosed and treated by nurse practitioners and physician’s assistants. Prices for treating common illnesses at these two places range from $62 to $145.

“The nurses have strict limitations,” says Linda Thompson, a family-practice physician in Bethesda. “But they know their boundaries and will quickly send someone to the emergency room.”

Dr. Thompson helped organize the adult-care practice at the Nighttime Care Center in Rockville, which has nurses, physician’s assistants, and doctors on staff. Like most urgent-care centers, Nighttime offers flu shots and can prescribe medicines and fill prescriptions.

Walk-In Medical Care’s three Northern Virginia locations offer everything from hearing exams to lab testing for mononucleosis, sexually transmitted diseases, pregnancy, and more. Patients just need a photo ID and an insurance card.

Urgent-care centers and similar clinics best serve people by diagnosing them, says Dr. Thompson: “The average person doesn’t have medical training, so they may not realize how sick they are. These clinics act like a triage unit for doctors and can send people to the right place.”

This article first appeared in the April 2009 issue of The Washingtonian. For more articles from that issue, click here.