Vial Guide

Injection guide

How a subcutaneous injection is given with an insulin syringe: where it goes, how to rotate sites, the technique, and getting rid of needles safely.

This covers injections under the skin (subcutaneous), the route most compounds here use. Intramuscular injections, such as hCG on its label or Thymalin, go into muscle and should be taught by a clinician.

Where it goes

Subcutaneous means into the fatty layer between the skin and the muscle. MedlinePlus lists three areas: the belly below the ribs and above the hip bones, at least 2 inches (5 cm) from the navel; the outer thighs; and the upper arms, at least 3 inches (7.6 cm) below the shoulder and 3 inches above the elbow.

Subcutaneous injection areas and a rotation pattern Front view: the belly between the ribs and hip bones, keeping 2 inches clear around the navel, and the outer thighs. Back view: the upper arms. Right: the belly split into four quarters with eight numbered spots, each at least an inch from the last. FrontBack BellyOuterthighs Upperarms Belly rotation 12345678 Move each shot at least 1 inch (2.5 cm) from the last; keep 2 inches (5 cm) clear around the navel
Our drawing. Each compound page notes where its label or guides place the injection.

Rotate every time

  • Move each injection at least 1 inch (2.5 cm) from the last one. A simple pattern is to work around the belly in quarters, as in the drawing.
  • Keep shots 1 inch (2.5 cm) away from scars, and skip spots that are bruised, swollen or tender.
  • Don’t inject into skin that feels lumpy, firm or numb. MedlinePlus calls this a very common reason insulin stops working as it should.
  • Keep a note or chart of the spots you’ve used. The dose log can track them on this device.

Step by step

  1. PrepareWash your hands. Check the vial: mixed solution should be clear. Draw up the dose; the reconstitution guide shows how to read the syringe.
  2. Clean the siteWipe the skin with an alcohol pad, starting where you’ll inject and circling outward. Let it air-dry.
  3. PinchPinch up about an inch (2.5 cm) of skin and fat, not muscle.
  4. InsertPut the needle in quickly, all the way, at 90 degrees, or at 45 degrees if there is little fat.
  5. InjectLet go of the pinch, push the plunger all the way, and leave the needle in for about 5 seconds before pulling it straight out.
  6. AfterPress clean gauze on the spot for a few seconds if it bleeds, then put the syringe straight into a sharps container.

Sources: MedlinePlus, Subcutaneous (SQ) injections and Giving an insulin injection (US National Library of Medicine, reviewed 2024).

Needles and sharps

  • Use a new needle and syringe every time. Never reuse or share them.
  • Put used sharps straight into a sharps container. FDA-cleared containers are sold at pharmacies and medical suppliers; FDA says a heavy-duty plastic household container, such as a laundry detergent bottle, can stand in.
  • When the container is about three-quarters full, get rid of it the way your community requires, such as a drop-off site or a mail-back program.
  • Never put loose needles in the trash or recycling, and never flush them.

Source: FDA, Safely using sharps (needles and syringes) at home, at work and on travel, and Best way to get rid of used needles and other sharps.

Stop and get medical help

Trouble breathing, swelling of the face or throat, chest pain or fainting after an injection is an emergency. Redness that spreads, heat, pus or fever at a site can mean infection.

By Vial Guide editorsLast reviewed

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