Long before he was Dr. Noah Drake in "General Hospital," Rick Springfield had explored and refined the art of infectious pop. But 10 years ago nobody was buying his prescriptions. The pulse as well as the beat went on, however, and now Springfield's catchy, hard-edged melodic pop is a dominant sound on the radio and in record sales.

At the Merriweather Post Pavilion last night, before a screaming crowd of 12,000, Springfield performed an 80-minute set that had as many ups, downs and turnarounds as an hour-long soap opera.

Like the skilled surgeon he portrays on TV, Springfield at first diagnosed the causes and after-effects of that most dreaded disease, love, in terse mini-soaps, sutured with singing guitar lines and sealed in airtight (though occasionally repetitious) frames. His songs show too much of a tendency to include the words "girls," "love" and "flash" or "night/right," as in "Love Is All Right Tonight." These songs are not overly ambitious in structure or content; like a cold, they tend to stay with you if you're not careful.

As a performer, Springfield has obviously benefited from his acting experience; he moves around the stage like a gazelle, a swirling, energetic catalogue of rock 'n' roll moves, smoothly delivered to screams that punctuated his songs like a high-pitched backbeat. One didn't need a stethoscope to note the throbbing hearts in Columbia. All in all, Rick Springfield turned out to be just what the nurses ordered.