Meet Our Physicians

Donald T. Ellenburg, M.D.

Dr. Ellenburg received his medical degree at the University of Tennessee Health Science Center. After completing medical school, Dr. Ellenburg competed three years of general pediatric training at the University of Louisville Children’s Hospital. Following his general pediatric training, Dr. Ellenburg completed two additional years of allergy fellowship at the University of Louisville. During his allergy fellowship, Dr. Ellenburg was also broadly trained in pediatric chest disease. Dr. Ellenburg founded the Cystic Fibrosis Clinic in East Tennessee and is its current medical director. Dr. Ellenburg has also long been associated with the American Lung Association of Tennessee and founded Camp Wezbegon, which helps aide in the transition of care from parent to youngster. As the field of allergy and clinical immunology is an ever-increasing broad span of information, Dr. Ellenburg continues to update his knowledge with yearly professional meetings as well as independent reading.

Timothy C. Frazier, DPh, M.D.

Dr. Frazier received his undergraduate degree at the University of Tennessee, Knoxville in Agriculture and further medical training at the University of Tennessee, Memphis in Pharmacy. Dr. Frazier received his medical degree from East Tennessee State University. Dr.Frazier’s residency was completed at the University of Louisville, Louisville, Kentucky in both internal medicine and pediatrics where he served as Chief Resident. Dr. Frazier completed a two-year allergy and immunology fellowship at the Medical College of Georgia in Augusta. Dr. Frazier continues to update his knowledge with yearly professional meetings as well as independent reading.

Andrew M. Singer, M.D.

Dr. Singer joined our practice in 2007 after serving as clinical instructor in the Division of Allergy & Immunology in the Department of Internal Medicine and in the Division of Pulmonology in the Department of Pediatrics at the University of Michigan in Ann Arbor, Michigan. Dr. Singer received his Bachelor of Science in Biology and his medical degree from Indiana University. Dr. Singer went on to complete his residency at Children's Hospital Medical Center in Cincinnati, Ohio. Dr. Singer then completed his fellowship in allergy and immunology at the University of Michigan. Dr. Singer continues to update his knowledge with yearly professional meetings as well as independent reading.