Dr. Hajjar received his medical degree at Damascus University School of Medicine. He finished his training in Internal Medicine from UPMC Shadyside and a Pulmonary/Critical Care fellowship from UPMC and the University of Cincinnati. He has been practicing in the Cincinnati area since 2000 and finished 10 years of practice as Pulmonary Director at Mercy Fairfield Hospital.

Dr. Hajjar is board certified in Pulmonary Medicine, Critical Care and Internal Medicine. Fellow of American College of Chest Physicians. Dr. Hajjar joined Pulmonary Medicine of Dayton in 2019.

He is married to Amal Sarah, M.D., a family physician in Mason Ohio and they have 3 children. Dr. Hajjar enjoys outdoor activities, especially playing Tennis and Soccer.