The most common initials that follow a doctor's name are M.D., which stand for medical doctor, according to Prevea Health. The initials help to identify the doctor's credentials, the type of medical school attended, and the exam taken to secure a medical designation.
The initials D.O. stand for doctor of osteopathy. This physician's credentials include a medical degree with a focus on muscular and skeletal systems to treat the entire body, Prevea Health explains.
Both types of doctors have attended medical school to become licensed, practicing doctors. Both are qualified in treating diseases and prescribing medication equally, Prevea Health notes. After receiving a medical degree or doctor of osteopathy degree, a doctor can become a specialist in certain areas of medicine.