Dr. Munnings attended Queens College, Nassau and McGill University in Montreal, before he graduated from the University of the West Indies faculty of Medicine in Mona, Jamaica. He obtained specialty training in Internal Medicine and Gastroenterology as a Commonwealth Scholar at the Bristol Royal Infirmary in England, under the late Professor Alan Read and Dr. Ken Heaton. He became member of The Royal College of Physicians of the United Kingdom and upon completion of his training, returned home to the Bahamas to practice.

Dr. Munnings is the medical director of Grosvenor Medical Centre, consultant gastroenterologist at Princess Margaret Hospital and at Doctor's Hospital, and is a lecturer for the University of the West Indies faculty of medicine. He is a member of the American College of Gastroenterology, the American Gastroenterological Association, the Florida Gastroenterologic Society and the Association of West Indian Gastroenterologists.