Founded in 1979 to offer home healthcare services: The first company to bring complex intravenous therapies out of the hospital into the home, allowing patients who had been hospitalized for weeks or indefinitely to receive therapy in a safe, comfortable, environment—their own homes, or on vacations and away at school. Caremark grew from a startup to a company with over $2 billion in revenues, serving hundreds of thousands of patients annually.

According to an article in the New York Times, Sweeney founded Caremark (originally Home Health Care of America) after he “… realized that a considerable number of hospital patients requiring intravenous therapy and nutrition did not really need to be hospitalized.”

The company was profitable in six months and within seven years had opened 75 centers around the U.S. CVS ultimately acquired Caremark in 2007 for $24 billion.