A PA in the medical field is a physician assistant (increasingly called physician associate), a licensed healthcare provider who diagnoses illnesses, develops treatment plans, and prescribes medications. PAs practice in virtually every medical specialty, from family medicine and emergency departments to surgery and dermatology. With a median salary of $133,260 as of May 2024 and projected job growth of 20 percent over the next decade, it’s one of the fastest-growing healthcare professions in the United States.
What PAs Actually Do
PAs function much like physicians in day-to-day clinical care. They take patient histories, perform physical exams, order and interpret lab work and imaging, diagnose conditions, prescribe medications, and assist in surgery. In many primary care offices, urgent care clinics, and emergency rooms, a PA may be the provider you see for your entire visit.
The scope of what a PA can do varies by state and practice setting. Some states have adopted what the American Academy of Physician Associates calls “optimal team practice,” which removes the legal requirement for a formal supervisory relationship with a specific physician. In those states, PAs practice with a high degree of independence. Other states still require a collaborative or supervisory agreement with a physician, though in practice this often means the physician is available for consultation rather than standing in the room.
PAs are trained as generalists first, then specialize on the job. This is a key distinction from nurse practitioners, who choose a specialty during their graduate program. A PA can move from orthopedics to cardiology to emergency medicine over the course of a career without returning to school, which gives the profession unusual flexibility.
How PA Training Works
PA programs are graduate-level and typically take 24 months to complete. Most require applicants to already hold a bachelor’s degree and have substantial direct patient care experience before applying, whether as EMTs, medical assistants, nurses, or in similar roles.
The curriculum follows what’s called a medical model, meaning it mirrors the structure of medical school rather than nursing school. The first year focuses on classroom and lab instruction in anatomy, pharmacology, pathophysiology, and clinical medicine. The second year is almost entirely clinical rotations, where students cycle through specialties like internal medicine, surgery, pediatrics, psychiatry, women’s health, and emergency medicine. These rotations typically require 40 to 50 hours per week of supervised patient care.
This broad, rotation-based training is deliberate. PAs are educated to be generalists who can work across specialties, diagnosing and treating a wide range of conditions rather than focusing narrowly on one body system or patient population.
Certification and Ongoing Requirements
After graduating from an accredited program, PAs must pass the Physician Assistant National Certifying Exam (PANCE) to earn the credential “PA-C,” which stands for physician assistant, certified. This exam is the gateway to licensure in every state.
Maintaining certification runs on a 10-year cycle, broken into five two-year periods. During each two-year cycle, a PA must complete and log 100 hours of continuing medical education. At least half of those hours must come from more rigorous, structured learning activities. The system incentivizes certain types of education: self-assessment activities earn 50 percent bonus credit, and practice improvement credits are doubled for the first 20 logged in each cycle.
PA vs. Nurse Practitioner
PAs and nurse practitioners (NPs) often fill similar roles in clinics and hospitals, which is why the two professions are frequently compared. The core difference is philosophical and educational. NPs are trained in a nursing model that emphasizes holistic, patient-centered care, preventive health, and emotional support alongside clinical treatment. PAs are trained in a medical model centered on diagnosing and treating specific diseases, closely paralleling how physicians learn.
The path into each profession also differs. NPs must first become registered nurses and gain clinical nursing experience before entering a graduate NP program, where they choose a specialty like family practice, acute care, or psychiatric mental health. PAs enter a generalist program regardless of their prior clinical background and specialize only after graduation, through their choice of job. Both can prescribe medications, order tests, and manage patients independently or collaboratively depending on state law.
Origins of the Profession
The PA profession was born out of a practical problem: a shortage of primary care physicians in the 1960s. Dr. Eugene Stead at Duke University recognized that military medics returning from the Vietnam War had extensive medical training but no civilian credential to match their skills. In 1965, he launched the first PA program at Duke, enrolling four Navy corpsmen in a curriculum that built on their existing knowledge with nine months of medical coursework and 15 months of clinical rotations. The first class graduated on October 6, 1967.
The profession has grown dramatically since then. There are now more than 300 accredited PA programs across the country, and the job market continues to expand as healthcare systems rely on PAs to improve access to care.
The Title Change: Assistant to Associate
In 2021, the American Academy of PAs voted to change the profession’s official title from “physician assistant” to “physician associate,” a move intended to better reflect the autonomous, collaborative role PAs play in modern medicine. The shift is ongoing and uneven. The National Commission on Certification of Physician Assistants now treats “physician assistant,” “physician associate,” and “PA” as interchangeable for certification purposes, but the legal title still depends on individual state law. In practice, you’ll see both terms used, and “PA” remains the universal shorthand regardless of which full title a state recognizes.