DO stands for Doctor of Osteopathic Medicine, one of two medical degrees that qualify someone to practice as a fully licensed physician in the United States. The other is an MD, or Doctor of Medicine. DOs can prescribe medication, perform surgery, and specialize in any field of medicine, just like MDs. The key difference is their training includes an additional focus on the musculoskeletal system and a hands-on treatment method called osteopathic manipulative treatment.
How DO Training Compares to MD Training
Both DO and MD programs are four-year medical school curricula with a similar structure: roughly the first two years in classrooms and labs, followed by two years of hands-on clinical rotations in hospitals and clinics. Both paths require completing a residency after graduation before practicing independently. The core clinical rotations overlap almost entirely, covering emergency medicine, family medicine, internal medicine, surgery, pediatrics, psychiatry, and obstetrics and gynecology.
The main curricular difference is that DO students also take coursework in osteopathic principles and practices throughout all four years, including training in manual diagnosis and treatment techniques. Many DO programs also emphasize community-based clinical training. A required rotation in a rural or underserved area during the fourth year is common at osteopathic medical schools, reflecting the profession’s roots in primary care and whole-person medicine.
For licensing, DO graduates take the COMLEX-USA exam, administered by the National Board of Osteopathic Medical Examiners, rather than (or sometimes in addition to) the USMLE that MD graduates take. Both exams are accepted by state medical boards, and since 2020, all residency programs operate under a single accreditation system, meaning DO and MD graduates compete for the same training positions.
The Osteopathic Philosophy
Osteopathic medicine is built on four core principles recognized by the American Osteopathic Association. The first is that the body is a unit of body, mind, and spirit, not a collection of separate parts. The second is that the body is capable of self-regulation and self-healing. The third is that structure and function are connected: how your body is built affects how it works, and vice versa. The fourth is that effective treatment should be based on understanding all three of these ideas together.
In practice, this means DOs are trained to consider how a problem in one part of the body might affect another, and to think about lifestyle, mental health, and environment alongside the specific condition they’re treating. This doesn’t mean MDs ignore these things, but the osteopathic curriculum formally builds this framework into every stage of training.
What Is Osteopathic Manipulative Treatment?
The most distinctive clinical skill DOs learn is osteopathic manipulative treatment, or OMT. It’s a set of hands-on techniques where the physician moves muscles and joints using stretching, gentle pressure, and resistance to diagnose and treat problems related to structural imbalance. The goal is to realign bones and muscles so the body functions better as a whole, improving blood flow and nerve signaling to affected areas.
Most people who receive OMT are seeking relief from lower back pain, neck pain, or migraines. But it’s also used for a surprisingly wide range of conditions:
- Respiratory issues like asthma and sinus infections
- Digestive problems like irritable bowel syndrome and constipation
- Chronic pain conditions including fibromyalgia and arthritis
- Pregnancy-related discomfort such as swelling, insomnia, and sciatica
- Musculoskeletal injuries including carpal tunnel syndrome and sports injuries
Not every DO uses OMT regularly in their practice. A DO who specializes in cardiology or psychiatry may rarely perform it, while a DO in family medicine or sports medicine may use it frequently.
DOs by the Numbers
About 11% of all actively licensed physicians in the United States hold a DO degree, according to a 2024 census by the Federation of State Medical Boards. That’s out of more than 1,082,000 total licensed physicians. While DOs are still a minority, their numbers have grown by 110% since 2010, making them the fastest-growing segment of the physician workforce.
DOs have historically been associated with primary care, and roughly 53% of osteopathic candidates matched into primary care residency programs in 2025. But the profession has diversified considerably. About 45% of DOs now practice in non-primary care specialties, including surgery, dermatology, radiology, and every other medical specialty you’d find an MD in.
Where DOs Can Practice
Within the United States, DOs have identical practice rights to MDs in all 50 states and the District of Columbia. They can prescribe controlled substances, admit patients to hospitals, lead surgical teams, and hold any medical position an MD can hold. For patients, the experience of seeing a DO is functionally the same as seeing an MD, though a DO may be more likely to incorporate hands-on assessment or OMT into a visit.
Internationally, DOs have full practice rights in more than 65 countries. However, recognition varies, and in some nations the DO degree is not as well understood or may require additional credentialing steps. The American Osteopathic Association maintains a country-by-country licensure map for DOs considering practicing abroad.
Origins of Osteopathic Medicine
The profession traces back to Andrew Taylor Still, a 19th-century physician and Civil War surgeon who grew disillusioned with conventional medicine after being unable to save members of his own family from disease. He rejected much of what he had been taught and began developing a new approach centered on the body’s structural integrity and its capacity for self-healing. In 1892, he founded the American School of Osteopathy in Kirksville, Missouri, in a two-room building. From that single school, the profession has grown to more than 40 accredited colleges of osteopathic medicine across the country.