U-100 insulin syringe (units)

A U-100 insulin syringe is the small, fine-needled syringe designed for insulin at a concentration of 100 units per mL. Its barrel is marked in "units," and that scale is really a volume: 100 units = 1 mL, 50 units = 0.5 mL, 10 units = 0.1 mL. The markings say nothing about how much medication is in that volume.

That distinction is the source of most compounded GLP-1 dosing errors. A prescribed dose in milligrams has to be converted to units using the concentration printed on your specific vial (for example, 2.5 mg/mL versus 5 mg/mL), and the same mg dose means a different number of units on each. The FDA has documented overdoses from people confusing units, mL, and mg. If you use a vial and syringe, have your pharmacist confirm the unit count for your dose and concentration. See reading an insulin syringe: units, mL, and mg for compounded GLP-1 doses.

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Reading an insulin syringe: units, mL, and mg for compounded GLP-1 doses — U-100 insulin syringes mark volume in "units" — 100 per mL — and your vial's concentration is what converts a prescribed mg dose into a unit count. This walkthrough teaches the arithmetic with worked examples at different concentrations, explains the FDA-documented error patterns, and gives a verify-with-your-pharmacist checklist. It teaches reading the syringe; it does not prescribe doses.

GLP-1 microdosing: what it means, why people do it, and what the evidence actually says — "Microdosing" GLP-1s is all over social media — using much smaller doses than the label calls for, for weight maintenance, side-effect avoidance, cost, or vague wellness claims. Here's what the term actually means, the kernel of real medicine it borrows from, why no clinical trial has tested it, the specific risks of the DIY version, and the legitimate way to have a lower-dose conversation with your prescriber.

Compounded GLP-1 dosing: vials and syringes vs. pre-filled pens — Compounded GLP-1 medications are typically dosed very differently than brand-name pens — often via vial and syringe, requiring you to measure your own dose. Here's why that raises the stakes on accuracy.

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U-100 insulin syringe (units)

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