Our Staff

Over 90 Years of Combined Clinical Experience

Dr. Harland Simpson, M.D.

Dr. Harland Simpson, M.D.

Anesthesiology, Pain Practitioner

“The reason I got into pain management is that, as a resident, I saw people who were dying and in pain,” Dr. Simpson said. “People were afraid to give them pain medication because they were dying. That was disturbing for me. But that was the practice of medicine 20 years ago.”

The doctor began his residency in anesthesia but spent the last six months in pain management. Back then, no fellowships were offered in pain management, according to Dr. Simpson, who was raised in Brunswick, Tenn., on the outskirts of Memphis.

After completing his education, including medical school at ETSU, Dr. Simpson joined the Army and served at the Lyster Army Health Clinic as chief of Anesthesia and Operative Services. He also started a pain clinic.

“The clinic became so popular that there were even generals who would fly in,” Dr. Simpson recalled. “It was a small base, Fort Rucker (in Alabama), and they were sending people to see me from all over the place.”

After three years, he left the Army ranked as a major and started working at Holston Anesthesia Associates where he was again asked to start a pain practice. Within three years, Dr. Simpson was seeing approximately 30 patients a day. The pain practice was eventually closed and Dr. Simpson stayed on with the anesthesia group for a few years. Then he moved to Indian Path Hospital, where he wanted to open another pain clinic. Once the clinic was opened, Dr. Simpson quit working in the hospital’s operating room as an anesthesiologist and concentrated solely on the pain clinic, which opened in September.

Dr. Leigh Anne Young Dunlap, M.D.

Dr. Leigh Anne Young Dunlap, M.D.

Advanced Pain Practitioner; Primary Care & Internal Medicine Provider
Dr Dunlap is an Internist who is board certified as an advanced pain practitioner through the American Academy of Pain Management

Dr. Leigh Anne Dunlap earned her Doctorate of Medicine from Quillen College of Medicine, ETSU. She completed a residency in internal medicine at the University of West Virginia and was board certified in internal medicine from the American Board of Internal Medicine. Following residency she moved to Ozark, Alabama setting up her first private practice, working both in the hospital and outpatient clinic for the next 3 years.  In 1996  she moved back to her home town, Kingsport, TN accepting a teaching position with East TN State University

 Following the birth of her first son Dr Dunlap moved to outpatient work at Mountain Home Veterans Administration. In 2000 she became the first chief of the new  primary care program at Mountain home , expanding the clinic from 5,000 to 27,000 veterans over the next 3 years. The next 7 years Dr Dunlap taught  and worked at the Friends in Need clinic in Kingsport. She rejoined Mountain home VA and  developed a rural outpatient clinic for veterans in Marion VA until she left to start her private practice with Simpson Clinic in 2014. 

  She has maintained a strong interest in the diagnosis and treatment  of chronic pain, credentialing in the area of chronic pain shortly after joining Simpson Clinic. She firmly believes in treating the whole patient both chronic disease states and the pain which is often generated from these diseases. 

     Dr Dunlap resides in Kingsport and enjoys music, spending time on she and her husbands boat, riding on the back of his motorcycle and  playing cello in her church orchestra.

Dr. Barb Overbay, M.D.

Dr. Barb Overbay, M.D.

Primary Care & Internal Medicine Provider

Dr. Overbay earned her BA in Microbiology at the University of Tennessee in 1985 and her MD degree at ETSU Quillen College of Medicine in 1990. She completed 3 years of Internal Medicine residency at Memorial Medical Center in Savannah, Georgia then returned to Quillen 2 additional years for subspecialty training in Infectious Diseases. During this time she served as rotating ward attending and instructor for the medical resident inpatient service. She successfully passed and was awarded board certification in both Internal Medicine and Infectious Diseases. After completion, she was hired by the Mountain Home VA in 1995 for their new developing program in primary care where she went on to care for our local veteran population for the next 25 years. Her interests are in the care of common chronic medical problems such as diabetes, heart disease, and copd. She places major emphasis on prevention and lifestyle management such as appropriate diet, exercise, weight management, smoking cessation, vaccinations, and cancer screening.


General interests include family time when possible, reading, gardening, cooking, hiking, and traveling.