Administration

Needle Gauge

The thickness of a needle — higher gauge number = thinner needle.

Definition

Needle gauge is inversely related to diameter: a 31 G needle is thinner than a 25 G needle. Subcutaneous peptide injection typically uses 29–31 G needles, 4–12 mm long, for minimal discomfort.

Related terms

Insulin SyringeA 1 mL or smaller syringe with a fine needle used for subcutaneous injection.
Subcutaneous Injection (SC)Injection into the layer of fat beneath the skin — the most common route for peptide administration.

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