In his final year of medical school, he was chosen to do clinical research at Peter Bent Brigham Hospital in Boston.

[5] In 1916, Levine was one of two young physicians recruited by the Harvard Infantile Paralysis Commission to cope with the caseload of that year's poliomyelitis epidemic.

[3]: 474 Levine was appointed assistant professor of medicine at Harvard in 1930,[5] and physician at Peter Bent Brigham Hospital in 1940.

[8] He was a noted teacher and trainer of heart specialists including Bernard Lown, and also helped diagnose pernicious anemia.

Named in his honor, the Samuel Albert Levine Cardiac Unit at Brigham and Women's Hospital opened in 1965.