The Department of Internal Medicine of DLSUMC is the specialty of medicine that covers a wide range of conditions affecting the internal organs of the body. At DLSUMC, the Department of Internal Medicine has a total of forty-one (41) active consultants and twenty-two (22) residents. Consultants are diplomates and fellows of thee Philippine College of Physicians. The following subspecialties are available in the hospital: Allergy and Immunology, Cardiology, Dermatology, Endocrinology, Gastroenterology, Hematology, Infectious Diseases, Nephrology, Oncology, Pulmonology, Neurology, and Rheumatology. It has an accredited residency training program under the Philippine College of Physicians. Moreover, it started an accredited fellowship training program for Adult Cardiology.