Infectious Disease, coded right.

99204 is the default code for most new-patient outpatient encounters in primary care and outpatient subspecialty practice. Use it for a new patient with at least one of: two or more chronic problems with progression or treatment changes; one undiagnosed new problem with uncertain prognosis; prescription drug management. Common patterns: new patient establishing primary care with multiple chronic comorbidities; new endocrinology consult for poorly controlled T2DM; new cardiology consult for chest pain and an abnormal stress test result. Prescription drug management satisfies moderate risk on its own, which makes 99204 the right code for the vast majority of new-patient continuity encounters. Time-based alternative is 45 to 59 minutes of total time on the date of the encounter.

Use 99205 for a new patient with severe, decompensated, or high-acuity disease, or for complex consult-style new-patient encounters where decisions about hospitalization, major surgery, drug therapy requiring intensive monitoring, or de-escalation of care are made. Real examples: a new patient referred for severe pulmonary hypertension where right-heart catheterization is planned; a new oncology consult for newly-diagnosed metastatic disease where systemic therapy is initiated; a new patient with decompensated heart failure where admission is considered. Time-based alternative is 60 to 74 minutes of total time on the date of the encounter. Beyond 75 minutes, add 99417 (commercial) or G0316 (Medicare) in 15-minute increments.

99214 is the workhorse of primary care and most outpatient subspecialties. Use it when at least one of these is true: two or more chronic problems with progression, treatment changes, or side effects; one undiagnosed new problem with uncertain prognosis; one acute illness with systemic symptoms; or prescription drug management at any complexity. Prescription drug management on its own satisfies the moderate-risk element, which is why straightforward chronic disease follow-ups with a med adjustment routinely clear the 99214 bar. Time-based alternative is 30 to 39 minutes of total time on the date of the encounter. Pick the method that supports the strongest note: encounters with prescription changes are usually cleaner under MDM; encounters with extensive counseling or care coordination are usually cleaner under time.

Use 99215 when the encounter genuinely required high-complexity decision-making: severe exacerbation or decompensation of a chronic illness, an acute or chronic illness or injury that poses a threat to life or bodily function, decision regarding hospitalization, drug therapy requiring intensive monitoring for toxicity, or extensive comorbidity management driving a high-risk decision. Real examples: a CHF patient with new bilateral leg edema and dyspnea where you considered emergency admission; a new-onset AFib with RVR you elected to manage outpatient with same-day rate-control titration; an oncology patient with febrile neutropenia. Time-based alternative is 40 to 54 minutes of total time on the date of the encounter.

G2211 is the continuity add-on. Append it to an office E/M (99202 through 99215) under one of two conditions: you are the continuing focal point for all of the patient's health care (the primary-care framing), OR you are the ongoing care provider for a patient's single serious condition or a complex condition (the subspecialty framing). Common eligible scenarios: a routine primary care follow-up for chronic disease management; an endocrinology continuity visit for diabetes; an oncology survivorship visit; a rheumatology disease-modifying-medication monitoring visit; a nephrology follow-up for CKD progression. Ineligible scenarios: one-time consults, urgent care visits, hospital follow-up where you are not the longitudinal provider, and visits where modifier 25 is appended to the primary E/M (explicitly prohibited).

Use 99417 as an add-on to 99205 or 99215 when total time on the date of the encounter exceeds the time threshold of the primary code by at least a full 15 minutes. Under current CPT rules 99205 requires 60 or more minutes, so the first 99417 unit applies at 75 minutes of total time; 99215 requires 40 or more minutes, so the first unit applies at 55 minutes. Each subsequent full 15-minute block is an additional 99417 unit. Typical scenarios: extended counseling for complex care planning, multi-system review on a complicated new patient, family meeting attached to an office visit, motivational-interviewing-heavy behavioral health follow-up. 99417 only attaches to 99205 and 99215; you cannot add it to 99213, 99214, 99203, or 99204. Medicare beneficiaries use G2212 instead, which starts counting later (89 minutes for 99205, 69 minutes for 99215). Verify your patient's payer before billing.

First therapeutic non-chemo IV infusion at the encounter.

Each additional hour of the same therapeutic infusion.

Single IV push of a non-chemo drug.

Use G0316 for Medicare patients when total time on the date of a hospital encounter exceeds the maximum time of the highest-level inpatient or observation code by at least a full 15 minutes. CMS trigger times: 99223 (initial hospital care, 75 minutes) supports the first G0316 unit at 90 minutes; 99233 (subsequent hospital care, 50 minutes) at 65 minutes; 99236 (same-day admission and discharge, 85 minutes) at 100 minutes. Typical qualifying encounters: a complex admission with multiple consultants, family meeting, and goals-of-care discussion; a deteriorating patient requiring repeated bedside reassessment and coordination across a long shift. Count all qualifying physician or QHP time on the calendar date, including documentation and coordination performed outside the patient's room. The primary code must be selected on time for prolonged services to apply.