Starting as a small office in Sandy Springs, Atlanta Allergy & Asthma Clinic has grown to 19 metro Atlanta locations.

Last month the practice celebrated its 40th anniversary.

“I was just treating a lady today in her 50s who has been coming to Atlanta Allergy since she was 11 years old,” said Dr. Kathleen Sheerin, who has worked at the practice for 20 years.

Sheerin said she believed it had been so successful because of the founders’ progressive thinking.

“Some of the original founders had the foresight to know that Atlanta was going to spread,” she said. “Forty years ago, Alpharetta was just farmland.”

Today there are clinics stretching from Stockbridge to Rome.

“I think it’s important in the allergy world to have a lot of clinics like that, because when you’re going to get allergy shots every week, you really don’t want to have to drive an hour for it,” she said.

Dr. Dennis Spangler, a founding doctor at the practice, started working at the clinic in the 1970s until his retirement in January.

“I feel the clinic has provided the Atlanta area with a forward-thinking allergy practice dedicated to providing the best and most convenient care to the residents of North Georgia,” he said.

Sheerin said the practice is also a certified pollen-count office with technicians certified to read the pollen count.

“When you see the pollen count on the news or in the paper, it’s coming from us,” she said.