Walgreen had 51 clinics in 2007 and runs 372 now. A spokesman said the company expects "double digit percentage growth" in the number of clinics this fiscal year, which ends in August. He declined to be more specific.
Aside from drugstores, patients also can find clinics in grocery stores, malls and some Wal-Mart and Target stores. Proponents say they can be more convenient than a doctor's office because they are open on weekends and for longer hours.
They also are a less-expensive option than a doctor's office, urgent care center or emergency room, which is important for people with no insurance or coverage that makes them pay more upfront for care.
The clinics initially handled mostly minor medical conditions and immunizations but have expanded over the years to add things like school and camp physicals to their menu of services.
A few years ago, CVS Caremark started offering lab tests and education for people who generally have already been diagnosed by a doctor with a chronic condition. Earlier this year, its clinics expanded into acne consultations, with the company advertising that service on its website under the slogan, "We treat it so you can beat it."
CEO Larry Merlo also told analysts in February his company is testing clinic programs that help customers quit smoking or manage their weight.
Rite Aid Corp., the nation's third-largest drugstore chain, doesn't offer chronic illness care at its small chain of clinics. But the company said last month it would start offering 10-minute online doctor consultations for $45 to store customers in several big cities.
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