How many units is a 500 mcg ARA-290 dose?

With a 10 mg ARA-290 vial reconstituted in 2 mL of bacteriostatic water (5 mg/mL, or 5000 mcg/mL), a 500 mcg dose works out to 500 divided by 50 mcg per unit, which is 10 units on a U-100 insulin syringe.

How much bacteriostatic water goes into an ARA-290 vial?

It depends on the concentration you want. A common reference point is 2 mL for a 10 mg vial, which gives 5 mg/mL and keeps typical research doses in a readable unit range. Use the calculator to test other volumes and find one that lands your dose on a round syringe mark.

Is ARA-290 FDA-approved?

No. ARA-290, also called cibinetide, is not FDA-approved for any use. It is sold as a research compound, not as a drug or supplement, and none of the figures in an ARA-290 reconstitution calculator describe an approved or recommended human dose.

Does an ARA-290 reconstitution calculator handle both mg and mcg?

Yes. Vial labels are almost always in milligrams while research protocols often describe doses in micrograms. 1 mg equals 1000 mcg, and the calculator converts between the two automatically once a vial size, water volume, and target dose are entered.

ARA-290 Reconstitution Calculator: Water & Syringe Math

By PeptCalc Research — Medically reviewed by David Mansour, MD — Last reviewed August 14, 2026

ARA-290 vials are labeled in milligrams, while research doses are usually written in micrograms — the exact conversion an ARA-290 reconstitution calculator is built to handle. This is a reference for the arithmetic behind that vial: how vial size and bacteriostatic water volume set concentration, and how concentration turns a target dose into an exact draw on a U-100 insulin syringe. It is written for research purposes only and is not medical advice.

What the calculator does

An ARA-290 reconstitution calculator only needs three numbers to do its job: vial size, water volume, and target dose. The peptide calculator handles the conversion in two directions:

Forward mode — enter vial size, water volume, and target dose, and it returns the syringe units to draw.
Reverse mode — enter vial size, target dose, and a desired unit count, and it returns the water volume that produces it.

Both modes run on the same formula: concentration equals mass divided by water volume, and units equal that volume in mL multiplied by 100 on a U-100 syringe. That formula doesn't change because the vial holds ARA-290 instead of another peptide — only the vial's own mass and water volume matter.

ARA-290 at a glance

ARA-290, also known as cibinetide, is an 11-amino-acid synthetic peptide corresponding to a small surface region of erythropoietin (EPO), the hormone the body uses to stimulate red blood cell production. ARA-290 was designed to bind only the receptor complex linked to EPO's tissue-protective signaling, not the receptor form responsible for red blood cell stimulation, which is why it is studied separately from EPO itself and described in the research literature as non-erythropoietic. That distinction is the basis for its research interest: exploring whether EPO's protective signaling can be isolated from its blood-forming effects. It has been studied in the context of nerve-related discomfort and metabolic stress, with the human research base smaller and more preliminary than its underlying mechanism data.

ARA-290 is not FDA-approved for any use. It is sold as a lyophilized research compound, not as a drug or supplement, and nothing here describes a use recommendation. It describes reconstitution arithmetic, which is identical regardless of a compound's regulatory status or how far along its research is. For a peptide with a comparably narrow, receptor-specific research focus, see the KPV peptide dosage calculator.

Typical research concentration

ARA-290 most commonly reaches researchers as lyophilized powder in vials in the 5 mg to 10 mg range. Reconstituted in 2 mL of bacteriostatic water, a reference point chosen because it keeps typical research doses on readable syringe marks:

Vial size	Water added	Concentration
5 mg	2 mL	2.5 mg/mL (2500 mcg/mL)
10 mg	2 mL	5 mg/mL (5000 mcg/mL)
20 mg	2 mL	10 mg/mL (10,000 mcg/mL)

These are reference points, not requirements — the peptide dosage calculator recalculates concentration for any vial size and water volume actually on hand.

The math

Step 1: Calculate concentration

Concentration = vial mass ÷ water volume

10 mg vial + 2 mL water = 10 ÷ 2 = 5 mg/mL (5000 mcg/mL)

Step 2: Convert concentration to mcg per unit

A U-100 insulin syringe divides 1 mL into 100 units, so:

mcg per unit = concentration (mcg/mL) ÷ 100

5000 mcg/mL ÷ 100 = 50 mcg per unit

Step 3: Convert the target dose to units

Units = target dose (mcg) ÷ mcg per unit

Worked example. A 10 mg ARA-290 vial reconstituted in 2 mL of bacteriostatic water is 5 mg/mL, or 5000 mcg/mL, which is 50 mcg per unit. A 500 mcg research reference dose from that vial is 500 ÷ 50 = 10 units. A 250 mcg dose from the same vial is 250 ÷ 50 = 5 units.

Compare that to a 5 mg vial in the same 2 mL of water: 5 ÷ 2 = 2.5 mg/mL, or 2500 mcg/mL, which is 25 mcg per unit. That same 500 mcg dose is now 500 ÷ 25 = 20 units — a larger draw from a lower-concentration vial, even though the dose in mcg hasn't changed at all.

Choosing a water volume

Water volume is the lever that sets how large a given dose reads on the syringe. For a 10 mg vial and a 500 mcg dose:

Water added	Concentration	mcg per unit	Units for 500 mcg
1 mL	10,000 mcg/mL	100 mcg/unit	5 units
2 mL	5,000 mcg/mL	50 mcg/unit	10 units
5 mL	2,000 mcg/mL	20 mcg/unit	25 units

None of these rows is more correct than another — 500 mcg is 500 mcg regardless of which row it comes from. A larger draw is generally easier to measure precisely on a U-100 barrel than a very small one, since a one-unit misread is a bigger proportional error at the low end. Reverse mode on the free peptide calculator finds the water volume that lands a specific dose on a round unit mark.

Reconstitution process

Gather the ARA-290 vial, bacteriostatic water, a U-100 insulin syringe, and alcohol swabs.
Swab both vial stoppers with alcohol.
Draw the water volume the chosen concentration calls for.
Inject it slowly down the inside wall of the vial, not directly onto the powder.
Swirl gently until fully dissolved — don't shake.
Confirm the resulting concentration matches what was entered into the calculator before drawing a dose.

For the general mixing walkthrough that applies to any peptide vial, see how to reconstitute peptides.

Storage

Reconstituted ARA-290 is generally kept refrigerated and protected from light. Unreconstituted lyophilized powder is far more stable than the mixed solution, which is why vials ship dry. Track the date each vial was reconstituted, particularly if more than one vial is in use at different concentrations.

Common mistakes

Confusing mg and mcg. ARA-290 vial labels are in milligrams; research doses are almost always described in micrograms. 1 mg equals 1000 mcg, and misreading one for the other produces a 1000x error.
Assuming ARA-290 behaves like EPO. ARA-290 was designed to avoid the receptor pathway responsible for red blood cell stimulation, so treating it as interchangeable with EPO in a research protocol misreads its intended mechanism.
Treating research figures as established human dosing. ARA-290's human research base is still developing relative to its preclinical evidence. A number appearing in a research protocol is not the same as a validated clinical dose.
Reusing a unit count across a different water volume. As the table above shows, 500 mcg is 10 units at one concentration and 20 units at another. A unit count only means something relative to the specific concentration it was calculated from.
Using a syringe that isn't U-100. Every unit conversion here assumes 100 units equal 1 mL. A different syringe scale changes the math entirely.

Used as an ARA-290 reconstitution calculator, the peptide calculator skips the arithmetic and returns exact syringe units, with reverse mode available for finding a water volume that lands a dose on a clean mark. For a peptide with a comparably narrow, receptor-specific research focus, see the KPV peptide dosage calculator.