Vasopressor Equivalent Dose Calculator

Q: Which equivalence formula does this calculator use, and why does that matter?

It uses the updated NEE equation of Kotani and colleagues (Critical Care 2023;27:29), as corrected in 2025. Published formulas disagree: the phenylephrine coefficient is 0.06 here but 1/10 in the 2021 Goradia scoping review, and the two angiotensin II factors differ fourfold even after the units are aligned. Always record which formula an NEE came from.

Patient Weight (kg) defaults to 70 — set this first

NE / Epi / Phenylephrine Order Units dopamine is always per kg

Vasopressin Order Units

Current Infusion Doses leave any agent at 0

Norepinephrine mcg/kg/min

Epinephrine mcg/kg/min

Phenylephrine mcg/kg/min

Dopamine mcg/kg/min

Vasopressin units/min (set above)

Angiotensin II ng/kg/min

Norepinephrine Equivalent

— mcg/kg/min

NEE expressed as a flat rate

— mcg/minfor charting and reporting — not a norepinephrine order

Contribution by Agent

Agent	Dose Entered	NEE addedmcg/kg/min	Share
Enter at least one infusion dose.

Do not program a pump from this number. NEE is a severity score, not a dose: never use it to convert one running vasopressor into another, and never hang it as a norepinephrine rate. The coefficients are group-level trial averages, not this patient’s response. Inotropes and mechanical support are not counted — on VA-ECMO or high-dose inotropes this figure is disproportionately low. Doses are read as norepinephrine base, the basis published scores are likely to mean; where a chart records salt weight instead, the true equivalent may differ up to twofold.

Show calculation steps

Recent Updates

A 2025 correction to the source paper changed the metaraminol coefficient from 8 to 1/8 — a 64-fold difference. It touches only metaraminol, so none of the six agents on this page is affected; an NEE quoted from the uncorrected text needs re-checking only if it included metaraminol.
The 2023 formula was the first to carry a factor for terlipressin, and it re-derived the angiotensin II factor from the multicentre ATHOS-3 trial rather than the 2012 single-center pilot used by the 2021 scoping review — which is why the two AT-II factors differ fourfold.

Sources: Kotani, Y., et al. Correction, Critical Care 2025;29(1):104 · the formula comparison is Table 1 of the 2023 original.

Key Knowledge Points

NEE answers one question: how much total vasopressor support is this patient on? It was built to standardize trial eligibility and describe shock severity when several agents run at once — not to guide titration or swap one drug for another.
A low NEE is not the same as being nearly off vasopressors. Vasopressin at 0.03 units/min scores only 0.075, yet that patient is still vasopressor-dependent and often becomes hypotensive on withdrawal. NEE describes exposure, not weanability, and must not decide de-escalation, line removal or level of monitoring.
One agent is not weight-scaled, and one uses a different mass unit. Vasopressin is multiplied as units/min, so 0.03 units/min adds 0.075 mcg/kg/min to every patient regardless of size. Angiotensin II is per kilogram, but its coefficient was published for ng/kg/min — a thousand-fold trap. A units/hour rate typed into the units/minute box inflates that agent 60-fold.
The coefficients are not interchangeable between formulas. This page uses Kotani 2023 as corrected in 2025; its phenylephrine factor is 0.06 where the 2021 Goradia review uses 1/10. The authors themselves write that “with scarce evidence, the conversion ratio for each vasopressor agent is determined arbitrarily”, and that NEE’s ability to predict worse outcomes has not yet been validated.
Norepinephrine base does not exist commercially. The authors searched agency databases and canvassed colleagues across five continents: every marketed product is a salt, and salts seem on average half as potent as the base — a difference pharmacists would call one of dilution rather than potency. No guideline states which basis its numbers use.

About This Vasopressor Equivalent Dose Calculator

This Vasopressor Equivalent Dose Calculator converts several concurrently running vasopressors into a single norepinephrine equivalent dose (NEE) in mcg/kg/min, applying the updated equation of Kotani and colleagues (Critical Care 2023;27:29) as corrected in 2025, and showing what each agent contributes so the total can be audited rather than trusted blindly. Six agents are covered; the formula’s other five (terlipressin, metaraminol, methylene blue, hydroxocobalamin, midodrine) are omitted as unavailable in most units or, for methylene blue, assigned a factor the authors call arbitrary.

The Formulas Explained

NEE (mcg/kg/min) = Norepinephrine + Epinephrine + 0.06 × Phenylephrine + 0.01 × Dopamine
+ 2.5 × Vasopressin (units/min) + 0.0025 × Angiotensin II (ng/kg/min)

Norepinephrine, epinephrine and phenylephrine are entered in mcg/kg/min, so a flat order is divided by weight first: Dose (mcg/kg/min) = Dose (mcg/min) ÷ Weight (kg). Dopamine has no flat-rate form in this formula and is always per kilogram. An 80 kg patient on norepinephrine 0.1 mcg/kg/min, dopamine 5 mcg/kg/min, vasopressin 0.03 units/min and angiotensin II 20 ng/kg/min has an NEE of 0.1 + 0.05 + 0.075 + 0.05 = 0.275 mcg/kg/min. Multiplied by weight that is 22 mcg/min — the same score written in another unit for charting, not a norepinephrine dose that could be hung in place of these four infusions.

Each coefficient traces to a specific comparison. Epinephrine is assigned 1 because two randomized trials found the dose needed to reach the same mean arterial pressure target was similar. Dopamine is 1/100 from SOAP II, where its dose ran consistently 100 times that of norepinephrine. Vasopressin is 2.5 read directly off VANISH, where 0.06 units/min spared 0.15 mcg/kg/min (0.15 ÷ 0.06 = 2.5); VASST is consistent but only near 100 kg, because it reported norepinephrine as a flat mcg/min rate — which is why this term is weight-blind and credits a 45 kg patient the same 0.075. Angiotensin II is 0.0025 from ATHOS-3, where 20 ng/kg/min lowered the norepinephrine requirement by a mean 0.05 mcg/kg/min compared with placebo.

Clinical Interpretation & Limitations

NEE exists because modern shock is treated with combinations. Once a patient is on norepinephrine plus vasopressin plus angiotensin II, no single infusion rate describes the support being given, and eligibility criteria written as “norepinephrine above X” stop working. One scale makes severity comparable across patients and centers — including where norepinephrine itself is unavailable.

What the number is not. It is not a target, not a titration guide, and not a conversion table for switching agents at the bedside. The equivalences were derived from group means in trials with different populations, targets and eras; an individual patient’s response to phenylephrine is not 0.06 of their response to norepinephrine. Equal NEE does not mean equal patient — because vasopressors differ in inotropic effect and interact with vascular tone, volume state and contractility, the authors note that “similar MAPs may correspond to very different hemodynamic profile despite comparable NEE”. An NEE of 0.4 built from epinephrine is a different patient from an NEE of 0.4 built from phenylephrine.

It under-states some patients badly. The formula counts vasoconstrictors only. A patient on veno-arterial ECMO with high-dose inotropes and low-dose norepinephrine has a low NEE that misrepresents the true intensity of hemodynamic support, and the authors say NEE must be used and interpreted cautiously in that population. Inotropes such as dobutamine and milrinone are not part of the equation at all.

Which formula produced a published NEE

Reported NEE values are not comparable unless the formula is stated. Older equations differ structurally: VASST 2008 and Gutsche 2017 mix flat mcg/min for norepinephrine with weight-based mcg/kg/min for dopamine in one line, and the published vasopressin factor ranges from 2.5 to 500 (Ralib 2013), partly a units difference and partly outright disagreement — Brown 2013 uses 5 where this formula uses 2.5. Both are tabulated in Table 1 of the source paper. Cite the equation with any NEE you quote.

Limitations

Adults only, and the source trials are not homogeneous: the phenylephrine factor rests on one small non-randomized septic-shock study and one randomized trial in patients under spinal anesthesia, and published phenylephrine ratios span 1.1 to 16.3. It is the least secure term here.
No severity bands are shown. The source paper defines no threshold for high-dose or refractory shock, so this page assigns none; any cut-off you have seen comes from a local protocol or an individual trial, not from this equation.
Five agents in the published formula are omitted here; no formula covers steroids or mechanical support comparably. Weight entry stops at 199 kg, the house limit across these calculators.
The base-versus-salt ambiguity is unresolved internationally and can move the result twofold. The offset is systematic, so trends within one patient or unit stay valid; comparison against a published NEE does not.

Frequently Asked Questions (FAQ)

1. What is a norepinephrine equivalent dose?

Norepinephrine equivalence (NEE) expresses several vasopressors running at once as the single norepinephrine dose of comparable potency, so total vasopressor support can be stated as one number. Studies use it as an eligibility criterion and an outcome measure. It describes exposure, not weanability, and its ability to predict outcome has not yet been validated.

2. Which equivalence formula does this calculator use, and why does that matter?

It uses the updated NEE equation of Kotani and colleagues (Critical Care 2023;27:29), as corrected in 2025. Published formulas disagree: the phenylephrine coefficient is 0.06 here but 1/10 in the 2021 Goradia scoping review, and the two angiotensin II factors differ fourfold even after the units are aligned. Always record which formula an NEE came from.

3. Why does the vasopressin contribution not change with body weight?

Vasopressin is ordered as a fixed rate in units per minute, not per kilogram, so the published coefficient of 2.5 multiplies units/min directly. At 0.03 units/min the contribution is 0.075 mcg/kg/min for every patient. Every other agent, angiotensin II included, is normalized per kilogram first, so weight moves those terms but not this one.

4. Is there an NEE threshold that defines high-dose or refractory shock?

Not in this formula’s source. The paper proposing the equation sets out no cut-off, and this calculator deliberately shows no color bands and no risk categories, because assigning one would mean inventing a threshold no trial validated. Local protocols and individual trials do define high-dose support, but not as part of this equation.

5. Does the norepinephrine base or salt formulation change the result?

It can, by up to twofold. The formula’s authors report that norepinephrine base is not marketed anywhere, that every product is a salt, and that salts seem on average half as potent as the base — a difference pharmacists would call one of dilution rather than potency. They state it is unknown which basis published scores mean.

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📖 Sources:

📝 How to cite this page:

DosePilot Medical Team. Vasopressor Equivalent Dose Calculator. DosePilot. Published August 16, 2026. Last medically reviewed August 2026. https://dosepilot.com/calc/vasopressor-equivalent-dose-calculator/

⚠️ Disclaimer:

This tool is for informational and educational purposes only and is not a substitute for professional clinical judgment. Norepinephrine equivalence is a research and severity measure whose conversion factors are derived from group-level trial data; it must not be used to titrate an infusion, to substitute one vasopressor for another, or to judge readiness for weaning. All treatment decisions must be made by a qualified healthcare professional considering the individual patient’s full clinical context.