EPO Dosing Calculator
Erythropoietin dose from hemoglobin and target level.
About this calculator
This calculator estimates a starting erythropoiesis-stimulating agent (ESA) dose for CKD-related anemia, based on the KDIGO 2012 anemia-in-CKD guideline's dosing framework together with the FDA-approved product labeling for the two ESAs in question: 50-100 units/kg of epoetin alfa per dose, given three times weekly for hemodialysis patients (the Epogen starting-dose range), alongside a separately calculated darbepoetin alfa starting dose (0.45 mcg/kg/week, the Aranesp label's own starting-dose figure, scaled by the same severity adjustment epoetin uses -- computed directly rather than converted from the epoetin dose via a units-to-mcg ratio, since a fixed conversion ratio compounds the epoetin severity multiplier a second time and overstates the darbepoetin dose). The epoetin dose scales directly with body weight, and steps up to the higher end of the range when the current-to-target hemoglobin gap exceeds 2 g/dL, or down when hemoglobin is already at or above target. Iron sufficiency is checked separately (TSAT 20% or higher AND ferritin 200 ng/mL or higher) before ESA therapy is considered appropriate -- ESAs are far less effective, and iron deficiency should generally be corrected first, in an iron-deficient patient.
Note that the 200 ng/mL ferritin threshold used here is the standard hemodialysis target; KDIGO's target for non-dialysis CKD patients is lower (100 ng/mL), and this calculator does not distinguish between the two populations, so it may flag a non-dialysis patient as iron-deficient more readily than guideline-appropriate. The estimated iron deficit uses the Ganzoni formula (weight x hemoglobin gap x 2.4, plus a 500 mg iron store assumption). This tool computes a STARTING dose only -- it does not perform the ongoing titration KDIGO describes (adjusting by roughly 25% based on the hemoglobin response over subsequent weeks), does not screen for ESA contraindications (uncontrolled hypertension, active malignancy, recent stroke or thrombotic event), and does not replace individualized anemia management under nephrology or dialysis-unit supervision.
Medical Disclaimer
This calculator is for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about your health. Never disregard professional medical advice or delay seeking it because of results from this tool.
This tool estimates a starting point only and is not a validated clinical decision-support system. It does not account for every patient-specific factor (organ function, drug interactions, allergies, comorbidities, or current clinical status). Any dose, rate, or setting must be independently verified by the treating clinician and pharmacist or respiratory therapist against current institutional protocols, product labeling, and the patient's full clinical picture before being administered or applied.
Inputs
Results
Epoetin alfa (units/week)
16,800
Figures current as of 2017. Sources: Kidney Disease: Improving Global Outcomes (KDIGO) Anemia Work Group. KDIGO Clinical Practice Guideline for Anemia in Chronic Kidney Disease. Kidney Int Suppl. 2012;2(4):279-335., Epogen (epoetin alfa) full prescribing information. Thousand Oaks, CA: Amgen Inc. FDA-approved labeling.
How to Use This Calculator
- Enter patient weight (kg), current hemoglobin (g/dL), and target hemoglobin (g/dL).
- Enter transferrin saturation (TSAT %) and ferritin (ng/mL) to assess iron status.
- Read the recommended weekly epoetin alfa dose (units/week) and per-session dose for thrice-weekly HD.
- Check iron replete status: ESA therapy should not start until TSAT >20% and ferritin >200 ng/mL.
How the result changes with Current Hemoglobin (g/dL)
| Current Hemoglobin (g/dL) | Epoetin alfa (units/week) |
|---|---|
| 4.5 | 21,000 |
| 6.75 | 21,000 |
| 14 | 7,875 |
| 20 | 7,875 |
What each input means
- Weight
- Patient body weight.
- Current Hemoglobin (g/dL)
- Current hemoglobin level.
- Target Hemoglobin (g/dL)
- KDIGO target 10-11.5 g/dL, not to exceed 13.
- Transferrin Saturation (%)
- TSAT: target > 20% before starting ESA.
- Ferritin (ng/mL)
- Serum ferritin: target > 200 for HD patients.
What each result means
- Epoetin alfa (units/week)
- Recommended weekly epoetin alfa dose.
- Epoetin per HD Session
- Per-session dose for thrice-weekly hemodialysis.
- Darbepoetin alfa (mcg/week)
- Equivalent weekly darbepoetin alfa dose.
- Iron Replete (1=Yes, 0=No)
- Whether iron stores are sufficient to support ESA therapy.
- Estimated Iron Deficit
- Ganzoni formula estimate of iron needed.
How this is calculated
Worked example, using the default values
- Identify Input Parameters4 parametersWeight (kg) = 70, Current Hemoglobin (g/dL) = 9, Target Hemoglobin (g/dL) = 10.5, Transferrin Saturation (%) = 15 = 5 input(s) provided
- Calculate Epoetin alfaEpoetin alfa = 80 * 3 * weight16800 = 16800
- Calculate Epoetin per HD SessionEpoetin per HD Session = round(epoetinWeeklyUnits / 3)5600 = 5600
- Calculate Darbepoetin alfaDarbepoetin alfa = 0.45 * weight, severity-adjusted31.5 = 31.5
Figures and sources
- KDIGO 2012 anemia-in-CKD guideline (ESA dosing framework, iron thresholds) (2012) — Kidney Disease: Improving Global Outcomes (KDIGO) Anemia Work Group. KDIGO Clinical Practice Guideline for Anemia in Chronic Kidney Disease. Kidney Int Suppl. 2012;2(4):279-335.
- Epoetin alfa starting dose, 50-100 units/kg three times weekly (hemodialysis) (2017) — Epogen (epoetin alfa) full prescribing information. Thousand Oaks, CA: Amgen Inc. FDA-approved labeling.
Engine last updated . Checked against 3 independently-derived tests — how we verify calculators. Built by Paul Gunder, a software engineer, not a licensed financial, medical, or legal professional.
Frequently Asked Questions
Why does a bigger gap between current and target hemoglobin lead to a higher starting dose?
When the hemoglobin deficit exceeds 2 g/dL, this calculator steps up from its standard starting dose to the higher end of the 50-100 units/kg per-dose range, reflecting more severe anemia that may benefit from a stronger initial push toward target. Conversely, if current hemoglobin is already at or above the target, the calculator drops to a reduced dose rather than continuing a full starting-dose regimen.
Do transferrin saturation and ferritin change the recommended EPO dose?
No -- TSAT and ferritin only affect the separate Iron Replete flag and Estimated Iron Deficit outputs, not the epoetin or darbepoetin dose itself. Clinically, though, iron status still matters: an iron-deficient patient generally needs iron repletion before or alongside ESA therapy, since ESAs are far less effective when iron stores can't support the increased red cell production they're meant to stimulate.
Why is the darbepoetin dose calculated separately instead of just converting the epoetin dose?
This calculator computes darbepoetin directly from KDIGO's 0.45 mcg/kg/week starting-dose figure, scaled by the same severity adjustment epoetin uses, rather than dividing the epoetin dose by a fixed units-to-mcg ratio. A fixed ratio would apply the severity step-up or step-down twice -- once inside the epoetin dose being converted, and again implicitly through the ratio itself -- overstating darbepoetin relative to its own published starting dose. Computing it independently keeps both ESA doses tied directly to their own guideline-referenced starting figures.
Does this calculator tell me how to adjust the dose after starting treatment?
No, it estimates a starting dose only. KDIGO-based titration calls for adjusting the dose over subsequent weeks based on the actual hemoglobin response -- typically reducing if hemoglobin rises too quickly or exceeds target, and increasing if the rise is inadequate -- which requires serial lab monitoring this calculator does not track.
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