Thank you for taking the time. That was more work than a reply usually is.
Insulin syringe graduations: U-100 syringes are marked in units where 100 units = 1 mL. Always confirm your syringe is U-100. Confusion between insulin units and milligrams is the most common syringe error.
The reasoning is more useful than the number, which is why I have shown it.
Grateful for the specificity. Vague answers to this question are what sent me looking.
Filter needles are for drawing from glass ampoules where particulate is a real risk. For a stoppered vial they add dead volume in exchange for very little.
On Dead volume across syringe I would separate what is worth knowing from what is worth acting on. The first list is long and the second is short, and conflating them is how threads get heated.
Needle length for subcutaneous delivery is a question about tissue depth and injection angle together. Short needles at ninety degrees and longer ones at an angle reach comparable depths.
It is worth stating the boring hypothesis before the interesting one.
Post #86 and I disagree about the size of the effect, not about the direction.
A detachable luer needle plus hub can retain enough volume to matter. Whether it matters to you depends on your dose, and the arithmetic is worth doing once.
The literature is thinner on this than the confidence in the thread implies.
I read post #90 twice before replying, because I had assumed the opposite.
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.
Read the full topic (99 posts)
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[2026 update] 0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters
On the subject in the title: 0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Working notes rather than a conclusion. A follow-up question about 0.3 ml versus 0.5 ml that I did not know to ask the…
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+108 | 124 | 27k | 2mo |
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Dead volume across syringe and needle combinations
On the subject in the title: Dead volume across syringe and needle combinations Working notes rather than a conclusion. Something about dead volume across syringe does not reconcile and I would like a second…
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Second pass at: Gauge and length selection for subcutaneous injection
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+50 | 58 | 14k | 15mo |
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+30 | 34 | 49k | 12mo |
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[2026 update] Dose numbers across compounds are not on the same scale
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