In medical terms, DO stands for Doctor of Osteopathic Medicine. It’s a full medical degree, equivalent in scope and practice rights to an MD (Doctor of Medicine). DOs can prescribe medication, perform surgery, specialize in any field of medicine, and practice in all 50 states. As of 2025, there are roughly 167,000 osteopathic physicians in the United States, making up about 11% of the total physician workforce.
How a DO Differs From an MD
The practical differences between a DO and an MD are smaller than most people assume. Both complete four years of medical school followed by residency training. Both can enter any medical specialty. Since 2020, DOs and MDs apply through the same residency match system, meaning they compete for the same training positions at the same hospitals.
The key distinction is philosophical. Osteopathic medical education is built around four core principles: the body functions as a single unit of body, mind, and spirit; the body can self-regulate and self-heal; structure and function are interconnected; and effective treatment accounts for all three of those ideas. In practice, this translates to additional training in the musculoskeletal system and a hands-on diagnostic and treatment method that MDs don’t learn.
Both degrees carry identical prescribing rights and surgical privileges. If you see a DO as your primary care doctor, cardiologist, or surgeon, they have the same legal authority and clinical scope as an MD in that role.
DO Education and Training
Osteopathic medical school is a four-year program. The first two years focus on biomedical and clinical sciences, while years three and four shift to hands-on clinical rotations in hospitals and clinics. The curriculum mirrors what MD students learn, with one addition: a subject called Osteopathic Principles and Practices, which runs through all four years. This is where students learn the manual examination and treatment techniques unique to osteopathic medicine.
For licensing, DO graduates take the COMLEX-USA (Comprehensive Osteopathic Medical Licensing Examination) rather than the USMLE that MD students take. Many DO students choose to sit for both exams, since some residency programs prefer one over the other. After medical school, DOs complete the same residency programs as MDs, training for three to seven additional years depending on their specialty.
Osteopathic Manipulative Treatment
The most distinctive clinical skill a DO brings is osteopathic manipulative treatment, or OMT. This is a set of hands-on techniques used to diagnose and treat musculoskeletal problems, and sometimes to support treatment of other conditions. A few common techniques include:
- Muscle energy: The physician guides you through specific movements that relax and lengthen muscles, improving range of motion and circulation.
- Myofascial release: Gentle, sustained pressure on the connective tissue surrounding muscles to relieve tightness and improve blood flow.
- Rib raising: A gentle lifting technique that stretches the tissue around the ribs, opening the ribcage to help the lungs expand more fully.
Not every DO uses OMT regularly. A DO who specializes in emergency medicine or psychiatry may rarely perform these techniques, while one in family medicine or sports medicine might use them daily. It’s an additional tool in their training, not a requirement of every patient visit.
Origins of Osteopathic Medicine
Osteopathic medicine traces back to a physician named Andrew Taylor Still, who founded the first osteopathic medical school in Kirksville, Missouri, in 1892. Still had served as a Civil War doctor and later lost family members to illness he couldn’t treat effectively. Those experiences drove him to search for better approaches to medicine, particularly ones that accounted for how the body’s structure affects its ability to heal. That founding philosophy still shapes DO training today, though the profession has fully integrated modern medical science, pharmaceuticals, and surgical techniques.
Choosing Between a DO and an MD
For patients, the choice between seeing a DO or an MD rarely matters in terms of quality of care. Both undergo rigorous training, pass national licensing exams, and maintain the same board certifications. If you’re choosing a doctor, their specialty, experience, communication style, and hospital affiliation are far more relevant than the two letters after their name.
Where DOs do stand out is in their additional training in the musculoskeletal system. If you’re dealing with chronic pain, mobility issues, or conditions where hands-on treatment could complement standard care, a DO may offer techniques that an MD wouldn’t. That said, plenty of DOs practice in specialties like cardiology, dermatology, and surgery where OMT plays little to no role.
One thing worth knowing if you travel: DOs trained in the United States hold full practice rights in more than 65 countries. However, the US-trained DO degree is not the same as an “osteopath” credential in countries like the United Kingdom or Australia, where osteopathy is a separate, non-physician profession focused exclusively on manual therapy. A US-trained DO is a fully licensed physician; an osteopath in many other countries is not.