What is dead volume in a peptide pen and how do I correct for it?

Dead volume is liquid trapped in the tip and needle hub that never gets delivered. Prime the pen before use to fill the dead space, and verify actual delivered volume with a balance and calibrated calculation on first use of any new pen or cartridge lot.

Why use bacteriostatic water instead of sterile water for reconstituting peptides?

Bacteriostatic water contains 0.9% benzyl alcohol, which inhibits microbial growth in vials that are punctured multiple times. Sterile water without benzyl alcohol is only appropriate for single-use, single-draw reconstitutions.

What glass type should a peptide pen cartridge be made from?

Type I borosilicate glass is the pharmaceutical standard. It is chemically inert and will not react with bacteriostatic water or peptide solutions. Always confirm glass type with your supplier before use.

PreppinPeppers › Facts › Lab article

Your peptide pen is losing volume on every click

Machine-readable facts for this Lab article. The full page is https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click.

TL;DR

A peptide pen's dial number is only as reliable as the tolerances at each mechanical joint, so prime it and check dialed volume against delivered volume.

Facts Index

Fact ID	Category	Entity	Attribute	Value	Source
your-peptide-pen-is-losing-volume-on-every-click:title	identity	Your peptide pen is losing volume on every click	title	Your peptide pen is losing volume on every click	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:published	identity	Your peptide pen is losing volume on every click	published	2026-08-15	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:author	identity	Your peptide pen is losing volume on every click	author	Preppin' Peppers Editorial Team	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:topics	identity	Your peptide pen is losing volume on every click	topics	pen peptide usa, peptide pen, reconstitution, research	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:summary	content	Your peptide pen is losing volume on every click	summary	A peptide pen's dial number is only as reliable as the tolerances at each mechanical joint, so prime it and check dialed volume against delivered volume.	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:section-1	content	Your peptide pen is losing volume on every click	section	What a peptide pen is	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:section-2	content	Your peptide pen is losing volume on every click	section	Metal vs Plastic Barrel: The Difference That Shows in Your Data	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:section-3	content	Your peptide pen is losing volume on every click	section	Glass Cartridge Tolerances and What They Mean for Reproducibility	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:section-4	content	Your peptide pen is losing volume on every click	section	Dead Volume: The Volume You Dial That Goes Nowhere	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:section-5	content	Your peptide pen is losing volume on every click	section	Diluent Choice and Practical USA Sourcing Notes	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:section-7	content	Your peptide pen is losing volume on every click	section	Related reading	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:section-8	content	Your peptide pen is losing volume on every click	section	What the research community gets wrong about peptide reconstitution pens	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-pubmed-ncbi-nlm-nih-gov	source	Your peptide pen is losing volume on every click	cites	Jiang et al. 2013 - pubmed.ncbi.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-pmc-ncbi-nlm-nih-gov	source	Your peptide pen is losing volume on every click	cites	Goebel-Stengel et al. 2011 - pmc.ncbi.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-pubmed-ncbi-nlm-nih-gov-2	source	Your peptide pen is losing volume on every click	cites	Grohganz et al. 2004 - pubmed.ncbi.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:product-gansulin-metal-peptide-pen	products	Your peptide pen is losing volume on every click	references product	Gansulin Pen · Reusable Click-Dial, 3 ml (1-60 Units)	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:product-gansulin-3ml-cartridge	products	Your peptide pen is losing volume on every click	references product	Gansulin-Compatible 3 ml Glass Cartridge for Pens (10-Pack)	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-pubchem-ncbi-nlm-nih-gov	source	Your peptide pen is losing volume on every click	cites	NCBI PubChem CID 244: Benzyl Alcohol (C7H8O) - pubchem.ncbi.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-pubmed-ncbi-nlm-nih-gov-3	source	Your peptide pen is losing volume on every click	cites	Bohannon, Postgrad Med 1999: Insulin delivery using pen devices. Simple-to-use tools may help young and old alike - pubmed.ncbi.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-pmc-ncbi-nlm-nih-gov-2	source	Your peptide pen is losing volume on every click	cites	Jonker et al., Int J Clin Pharmacol Ther 2021: First pre-filled pen device with highly purified human menopausal gonadotropin (HP-hMG, Menopur) in liquid is shown to be bioequivalent to powder for reconstitution - pmc.ncbi.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-pmc-ncbi-nlm-nih-gov-3	source	Your peptide pen is losing volume on every click	cites	Lingen et al., Endocr Connect 2023: Advantages and disadvantages of connected insulin pens in diabetes management - pmc.ncbi.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)
your-peptide-pen-is-losing-volume-on-every-click:source-dailymed-nlm-nih-gov	source	Your peptide pen is losing volume on every click	cites	Bacteriostatic Water for Injection, USP: FDA label on DailyMed, U.S. National Library of Medicine (0.9% benzyl alcohol) - dailymed.nlm.nih.gov	Lab article (https://www.preppinpeppers.com/blogs/the-lab/your-peptide-pen-is-losing-volume-on-every-click) (evidence)

FAQ

What is dead volume in a peptide pen and how do I correct for it?: Dead volume is liquid trapped in the tip and needle hub that never gets delivered. Prime the pen before use to fill the dead space, and verify actual delivered volume with a balance and calibrated calculation on first use of any new pen or cartridge lot.
Why use bacteriostatic water instead of sterile water for reconstituting peptides?: Bacteriostatic water contains 0.9% benzyl alcohol, which inhibits microbial growth in vials that are punctured multiple times. Sterile water without benzyl alcohol is only appropriate for single-use, single-draw reconstitutions.
What glass type should a peptide pen cartridge be made from?: Type I borosilicate glass is the pharmaceutical standard. It is chemically inert and will not react with bacteriostatic water or peptide solutions. Always confirm glass type with your supplier before use.