Becoming a Nuclear Medicine Physician

Quick Answer

There is more than one road into nuclear medicine, which is exactly why a student interested in it should not feel forced to choose all at once. You can train in nuclear medicine directly (a dedicated residency), or reach it through diagnostic radiology (a nuclear-radiology fellowship or an integrated pathway), or come to it from another specialty. All roads share one rule: a year of general clinical training first, then a defined block of nuclear medicine training, then board certification (ABNM, or ABR via nuclear radiology). This page maps the routes; details and durations follow current board requirements, which evolve — always confirm against ABNM/ABR before planning.

The universal prerequisite

Every pathway requires one year of preparatory clinical training in direct patient care (a clinical internship/PGY-1) before entering nuclear medicine training. Nuclear medicine physicians manage patients — especially now, in the therapy era — so a foundation in clinical medicine is required across every route.

The main pathways to ABNM certification

The principal routes (durations are the nuclear-medicine training components; confirm current specifics with the board):

The practical takeaway for a student: you can keep the radiology door open. Several pathways embed nuclear medicine inside or after diagnostic-radiology training, so exploring nuclear medicine is not a bet against radiology — it is often a route through it toward the therapeutic, molecular side of the field.

ABNM vs ABR — two boards, one field

Nuclear medicine physicians are certified either by the American Board of Nuclear Medicine (ABNM) or, for those trained through radiology, by the American Board of Radiology (ABR) in nuclear radiology. Both credential a physician to interpret nuclear studies and to deliver radiopharmaceutical therapy under the appropriate authorized-user requirements. International graduates have separate alternate pathways (an ABR alternate pathway with a minimum block of nuclear medicine training, and an ABNM route for those already certified in nuclear medicine abroad).

Authorized-user status — the therapy credential

Delivering radiopharmaceutical therapy requires authorized-user (AU) status under radiation-regulatory rules (in the US, the NRC / Agreement States, governed by 10 CFR Part 35). Training pathways build the supervised hours and case experience that qualify a physician as an AU for the relevant categories of therapy — the credential that actually lets you write directives and treat patients with ¹³¹I, ¹⁷⁷Lu, ²²³Ra, ⁹⁰Y, and emerging agents. As the field turns therapeutic, AU eligibility is central to what a nuclear medicine physician does. See the atlas's Dosimetry, Safety & Regulatory domain for the written-directive and AU framework.

For programs and residents

This atlas is built to serve training directly: an evidence-graded reference across every tracer, protocol, disease, and therapy; a high-yield layer aligned to the board blueprint; a study mode over hundreds of self-check questions; and the Correlative CT and Therapy & Theranostics depth that modern practice demands. It is designed to sit alongside a residency curriculum as the always-current knowledge base — free, comprehensive, and physician-reviewed.

Related pages

• Why Nuclear Medicine — the case for the field, for students deciding.
• The Therapy Transformation — why the workforce demand is surging.
• Dosimetry, Safety & Regulatory — the written-directive and authorized-user framework.

Key References

• American Board of Nuclear Medicine (ABNM) — initial certification training requirements.
• American Board of Radiology (ABR) — nuclear radiology subspecialty pathways (including the 16-month pathway).