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Reading a syringe in poor light, and how to avoid needing to

Devices › Syringes & needles syringe units dead volume needle gauge & length worked example

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Solved by r.mensa in post #2

Syringe barrel size: common sizes are 0.3 mL, 0.5 mL, and 1.0 mL. Smaller barrels are more legible for small doses. Larger barrels hold larger volumes. Choose based on your dose.

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c.rasmussenTL2 Moderator25 May 2026#1

Reading a syringe in poor light, and how to avoid needing to Writing it up because I had to work it out twice and would rather nobody else did.

Practical question with the units stated, because I have seen how quickly these go wrong without them.

I have a 2 mg vial of retatrutide and I am working to a 0.25 mg step. My syringes are U-100 insulin syringes, 0.5 mL barrel.

I can do the arithmetic and I have done it twice, getting the same answer both times, but I would like someone to check the reasoning rather than the number — specifically whether I have thought about the residual volume correctly, and whether the graduation I am landing on is one a person can actually read.

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r.mensaTL2 Moderator Solution1 Jul 2026#2

Syringe barrel size: common sizes are 0.3 mL, 0.5 mL, and 1.0 mL. Smaller barrels are more legible for small doses. Larger barrels hold larger volumes. Choose based on your dose.

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titration_diaryTL3Regular28 Jul 2026#3

I read the opening post twice before replying, because I had assumed the opposite.

Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own records is not any individual result; it is that they are dated and consecutive.

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