Botox Dilution Calculator and Reconstitution Chart

Vial size

Saline added

Preservative free 0.9% sodium chloride.

Dose to draw

units

The units you plan to give.

Units from different toxins are not interchangeable. Use the chart for the product in your hand.

Units per 0.1 mL

4units

100 units in 2.50 mL is 40.0 units per mL.

Units per 0.1 mL: 4.00
Units per 1 mL: 40.0
Volume for 20 units: 0.500 mL
U-100 insulin syringe marks: 50.0
Doses of that size per vial: 5.0

Chart

Botox reconstitution chart

Units per 0.1 mL for each vial size and saline volume. Same arithmetic for any vial; units are never swapped between products.

Botox reconstitution chart: units per 0.1 mL by vial size and saline volume
Saline	50 unit vial	100 unit vial	200 unit vial	300 unit vial
0.5 mL	10	20	40	60
1 mL	5	10	20	30
1.25 mL	4	8	16	24
1.5 mL	3.33	6.67	13.33	20
2 mL	2.50	5	10	15
2.5 mL	2	4	8	12
3 mL	1.67	3.33	6.67	10
4 mL	1.25	2.50	5	7.50
5 mL	1	2	4	6

How it works

The dilution math, step by step

Units per mL. Divide the units in the vial by the mL of saline you add. 100 units in 2.5 mL is 40 units per mL.

Units per 0.1 mL. Divide that by ten: 4 units per 0.1 mL. This is the number most charts and injection plans are written in.

Volume for a dose. Divide the dose by the units per mL. 20 units at 40 units per mL is 0.5 mL.

Syringe marks. A U-100 insulin syringe has 100 marks per mL, so the volume times 100 is the number of marks to draw to: 0.5 mL is 50 marks.

The calculator does the arithmetic only. Doses, injection sites, storage and the time a vial can be used after reconstitution come from the product label and the prescriber.

Questions

What injectors ask about this

How many units per 0.1 mL is 100 units of Botox in 2.5 mL?

4 units per 0.1 mL. That is the dilution in the BOTOX Cosmetic label for a 100 unit vial, and a 50 unit vial with 1.25 mL gives the same 4 units per 0.1 mL.

What if I reconstitute 100 units with 1 mL?

Each 0.1 mL then holds 10 units, so a 20 unit dose is 0.2 mL. Less saline means the same units in less volume.

How many units is one line on an insulin syringe?

A U-100 insulin syringe is marked in hundredths of a mL, so each line holds a tenth of your units per 0.1 mL. At 4 units per 0.1 mL one line is 0.4 units, and a 20 unit dose is 50 lines, or 0.5 mL.

What saline is used to reconstitute Botox?

The BOTOX Cosmetic label calls for sterile, preservative-free 0.9% sodium chloride. For storage and how long a reconstituted vial can be used, check the current prescribing information for the product you have.

Does this work for Dysport, Xeomin or other toxins?

The arithmetic works for any vial: units divided by saline. The units themselves are not interchangeable between products, so never convert a dose from one toxin to another with this calculator. Follow each product's own label.

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