GLPHubglpresearchhub.com
Read-only archive. GLP Research Hub is a static community record — nothing here is for sale, no account is needed, and no vote you cast is counted. Why?
Archived. This submission is more than a year old. Votes and new comments are closed, and some of the advice in it may have been superseded — check the community wiki for the current version.
3k

someone explain bacteriostatic water to me like I have not read a paper in years

PSA Cold Box ×2 The Quiet One ×3 Well Actually ×1

Trying to settle this properly because the thread from last year went in circles.

The claim: reconstitution matters. The counter-claim: it is measurement error. Both sides have been asserting it confidently for about 11 months without either producing anything.

What would actually settle it is 11 people measuring the same thing the same way. I have started; my numbers are below. They lean one way but not strongly enough for me to declare victory.

If you have data, post the data. If you have an opinion, flair it as an opinion.

3,733 up / 754 down83% upvoted35 commentsid 14nwhw13 May 2025

35 comments

30 in this archive, depth 5

best — the order this archive was captured in

u/karim_ilunga427 points·1 year ago

No. This is the kind of confident post that gets copied into a screenshot and repeated for years. Where is the evidence.

replysharereportpermalink
u/nadia_kjaer-4 points·1 year ago

i am begging people to write down the concentration

replysharereportpermalink
u/batch_number_bertievetting1 point·1 year ago

Did you write the concentration on the vial?

replysharereportpermalink
u/declared_value_dvOP0 points·1 year ago

more water means more units for the same dose, which means finer resolution

replysharereportpermalink
u/emil_zamora1 point·1 year ago

No. This is the kind of confident post that gets copied into a screenshot and repeated for years. Where is the evidence.

replysharereportpermalink
u/mateusz_achebe348 points·1 year ago

This is correct. 2mL versus 13mL is the common mistake.

replysharereportpermalink
u/vito_beaulieu156 points·1 year ago

show your working or it is unhelpful

replysharereportpermalink
u/niels_roos122 points·1 year ago

Edit to your parent would help — the concentration you quoted assumes one scenario and you have written another above it.

replysharereportpermalink
u/ilias_steiner96 points·1 year ago

dosing errors come from people reconstituting two vials differently and forgetting which is which

replysharereportpermalink
u/marisol_frisk168 points·1 year ago

This is the "correlation is mechanism" thing again. You changed three variables at once.

replysharereportpermalink
u/marta_weiss273 points·1 year ago·edited

This is correct. 3mL versus 2mL is the common mistake.

replysharereportpermalink
u/saskia_mwangi243 points·1 year ago

This is correct. 1mL versus 9mL is the common mistake.

replysharereportpermalink
u/rasmus_mensah170 points·1 year ago

5mg vial, 1mL water, concentration is 5/1 — write it on the vial afterwards

replysharereportpermalink
u/RetaAndRegret275 points·1 year ago

swirl, do not shake, or you are courting oxidation

replysharereportpermalink
u/declared_value_dvOP44 points·1 year ago

swirl, do not shake, or you are courting oxidation

Counter-anecdote: opposite result, same dose. Which mostly tells us the variance is huge.

replysharereportpermalink
u/hub_opssite staff54 points·1 year ago

show your working or it is unhelpful

replysharereportpermalink
u/escrow_evangelist197 points·1 year ago·edited

This is the "correlation is mechanism" thing again. You changed three variables at once.

replysharereportpermalink
u/declared_value_dvOP0 points·1 year ago

Cored the stopper on my 18th draw because I kept using the same entry point. Rotate the puncture site.

replysharereportpermalink
u/units_not_mgsyringe math84 points·1 year ago

never post a calculation as advice without stating the concentration

replysharereportpermalink
u/honest_syringe_maybe68 points·1 year ago

more water means more units for the same dose, which means finer resolution

replysharereportpermalink
u/rina_bergstrom149 points·1 year ago

Cosigning. The concentration on the vial in marker is load-bearing.

replysharereportpermalink
u/gradient_goblin50 points·1 year ago

Are you using a u-100 or u-40 syringe? That changes everything.

replysharereportpermalink
[deleted]20 points·1 year ago

[deleted]

replysharereportpermalink
u/liv_nkemelu13 points·1 year ago

never post a calculation as advice without stating the concentration

replysharereportpermalink
u/sigrid_kaufmann4 points·1 year ago·edited

never post a calculation as advice without stating the concentration

Yes, exactly this, and it is the bit that took me 6 weeks to accept.

replysharereportpermalink
load more comments (1) →
u/wanjiru_varga113 points·1 year ago

Cosigning. The concentration on the vial in marker is load-bearing.

replysharereportpermalink
u/yusuf_achebe61 points·1 year ago

Edit to your parent would help — the concentration you quoted assumes one scenario and you have written another above it.

replysharereportpermalink
u/oskar_kaufmann44 points·1 year ago

dosing errors come from people reconstituting two vials differently and forgetting which is which

replysharereportpermalink
u/swirl_dont_shakeMOD73 points·1 year ago

Removed a chain here. The rule is one line long and it is not negotiable.

replysharereportpermalink
Permalinked branches
Deep branches get their own page so a single reply chain can be linked and read on its own.
About c/reconstitution

The arithmetic and the technique. Bacteriostatic versus sterile water, reconstitution volume as a concentration choice, converting mg/mL into insulin-syringe units, dead space, swirl-not-shake, stopper coring, and how long a reconstituted vial is actually good for. Math errors get corrected fast and politely.

88kmembers
130submissions
Aug 2023created
submissions / month, last year
Sponsored

Sigma-Aldrich Standards

Certified reference materials for peptide identity and purity work.

sigmaaldrich.com
c/reconstitution rules
  1. Show your numbers. "How many units?" with no mg and no mL cannot be answered.
  2. Never post a calculation as advice without stating the concentration it assumes.
  3. No sterile-compounding-for-others discussion. Personal handling only.
  4. Independent community. Nobody here sells anything, and anyone who tries is banned.
  5. Not medical advice. Describe what you did; never prescribe to a stranger.
  6. Claims need evidence. Batch numbers, dated screenshots, independent test reports, or a citation.
  7. No referral links, discount codes or affiliate URLs. Permanent ban, no appeal.
  8. No contact handles, wallet addresses or tracking numbers — they identify people.
  9. Be recognisably decent. Disagree hard, insult nobody.
Moderators
Volunteers. Unpaid, unaffiliated, and reachable through modmail only.
Before you read on

Several compounds discussed on GLP Research Hub are sold for research use only and are not approved for human use anywhere. Nothing here is medical advice and none of it is written by your clinician. If a post reads like an instruction, treat it as a description of what one stranger did.