He is also an associate professor of medicine at Harvard Medical School. He received his medical degree from the University of the Philippines Manila (Manila, Philippines). He then completed a fellowship in internal medicine and a chief medical residency at The Brooklyn Hospital Center (formerly Brooklyn Hospital and Brooklyn - Caledonian Hospital). He also completed two fellowships: the first in pulmonary and critical care at West Virginia University Hospitals, and the second in pulmonary disease at BWH. He is board certified in critical care medicine, internal medicine and pulmonary disease.