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Peptide dosage calculator

Reconstitution maths for a target dose: concentration after mixing, volume to draw, and the mark to hit on a 100-unit insulin syringe. Presets are pulled from the same records that drive the compound pages, so they do not drift.

Read this first This is arithmetic, not a prescription. It tells you what volume corresponds to a dose you have already decided on with a clinician. It does not tell you what dose to take, and many compounds on this site are not approved for human use.
Concentration 2.5 mg/mL
Volume to draw 0.1 mL
On a 100-unit syringe 10 units
Doses per vial 20

How reconstitution works

Lyophilised peptides ship as a dry powder. Adding bacteriostatic water turns a known mass into a known concentration, and from there every dose is a volume. The calculator does three steps: vial mass ÷ water volume = concentration; target dose ÷ concentration = volume; volume × 100 = units on a U-100 insulin syringe.

Two errors cause most mistakes: mixing up micrograms and milligrams (a factor of 1,000), and using a syringe that is not U-100. Check both before you rely on any number.

Dosage calculator questions

How do you calculate peptide concentration after reconstitution?

Divide the milligrams in the vial by the millilitres of bacteriostatic water added. A 5 mg vial mixed with 2 mL gives 2.5 mg/mL, which is 2,500 mcg per mL.

How many units on an insulin syringe is my dose?

A 100-unit (U-100) insulin syringe holds 1 mL, so 1 unit is 0.01 mL. Divide the dose in mcg by the concentration in mcg/mL to get millilitres, then multiply by 100. At 2,500 mcg/mL, a 250 mcg dose is 0.1 mL, or 10 units.

Does adding more water change the dose?

No. More water lowers the concentration, so you draw a larger volume for the same dose. It can make small doses easier to measure accurately.

Where do the presets come from?

From the reported research ranges and typical vial sizes in each compound record in our directory. They describe the literature and are not a recommendation for any person.

References

Regulatory and primary sources

  1. FDA: Bulk drug substances that may present significant safety risks (Category 2 and withdrawn nominations) ↗ · content current as of April 22, 2026; checked October 18, 2026
  2. FDA: Bulk drug substances used in compounding under section 503A ↗ · how the 503A categories work
  3. FDA: Unapproved drugs ↗ · status of products sold "for research use only"
  4. WADA Prohibited List ↗ · peptide hormones and growth factors, class S2
  5. PubMed (National Library of Medicine) ↗ · source of every literature reference on this site

Published literature

  1. Kosinski TM, Brown MC, Zavala PJ. Sterile Basics of Compounding: Relationship Between Syringe Size and Dosing Accuracy.Int J Pharm Compd 2018.PubMed 29385385
  2. O'Mara K, Campbell C, O'Mara R. Comparison of Dosing Accuracy Between the ENFit LDT and a Neonatal-Specific ISO-Compliant Enteral Syringe.J Pediatr Pharmacol Ther 2023.PubMed 37303768 · doi:10.5863/1551-6776-28.3.255
  3. Krauthammer M, Harel G, Moisseiev E. SYRINGE DESIGN AND FILLING TECHNIQUE AFFECT ACCURACY OF ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR INTRAVITREAL INJECTIONS.Retina 2023.PubMed 36729828 · doi:10.1097/IAE.0000000000003693
  4. Itoh K, Negishi M. Measurement of Acute Intraocular Pressure Elevation Immediately After Intravitreal Anti-VEGF Injection and Analysis of Prefilled Syringe Accuracy.Clin Ophthalmol 2026.PubMed 41804317 · doi:10.2147/OPTH.S589783
  5. Sobhani P, Christopherson J, Ambrose PJ, et al.. Accuracy of oral liquid measuring devices: comparison of dosing cup and oral dosing syringe.Ann Pharmacother 2008.PubMed 18056832 · doi:10.1345/aph.1K420
  6. Moisseiev E, Rudell J, Tieu EV, et al.. Effect of Syringe Design on the Accuracy and Precision of Intravitreal Injections of Anti-VEGF Agents.Curr Eye Res 2017.PubMed 28306392 · doi:10.1080/02713683.2016.1276195

Literature retrieved from PubMed on October 18, 2026, favouring human studies and reviews. Numbered markers in the text show which paper supports which statement; uncited entries are background reading.