What Is a Subcutaneous Injection?

A subcutaneous injection delivers medication into the layer of fat just beneath the skin. It's the most common method for self-administering GLP-1 medications like semaglutide, insulin, peptides, and other hormones.

Unlike intramuscular injections, subcutaneous injections use shorter, finer needles (typically 31G, 6mm) and are considerably less painful. Most people describe the sensation as a brief pinch.

Choosing an Injection Site

The three most common sites for subcutaneous injection are:

  • Abdomen — the most popular choice. Inject at least 5cm away from your navel, in the fatty tissue to either side.
  • Front of the thigh — the upper outer area, about halfway between knee and hip. Easy to reach and see.
  • Upper arm — the fatty area on the back of the upper arm. Can be harder to reach on your own.

Rotate your injection sites each time to avoid tissue hardening. Move the injection point a few centimetres each time.

Step-by-Step Injection Process

  1. Wash your hands thoroughly with soap and water.
  2. Prepare your supplies — syringe, alcohol wipe, medication vial, sharps container.
  3. Clean the injection site with an alcohol wipe in a circular motion. Allow it to air dry completely (about 30 seconds).
  4. Draw the medication into your syringe. Check for air bubbles — tap them to the top and push them out gently.
  5. Pinch the skin at the injection site to lift the fatty tissue away from the muscle.
  6. Insert the needle at a 90-degree angle with a 6mm needle. Insert smoothly and quickly.
  7. Inject slowly — push the plunger down steadily.
  8. Wait 5-10 seconds before removing the needle to ensure all medication is delivered.
  9. Remove and dispose — place the used syringe immediately into a sharps container. Do not recap.

Managing Anxiety and Discomfort

  • Use the finest needle available — 31G needles are thinner than a human hair.
  • Inject at room temperature — remove your vial from the fridge 15-30 minutes before injecting.
  • Be quick and confident — a hesitant insertion hurts more than a decisive one.
  • Breathe — take a slow, deep breath as you insert the needle.

Aftercare

  • Apply gentle pressure with a clean tissue if you see a drop of blood — this is normal.
  • Do not rub the injection site — this can cause bruising.
  • Note the injection site and date so you can rotate next time.

Common Mistakes to Avoid

  • Not cleaning the site — always use an alcohol wipe and let it dry.
  • Injecting into muscle — pinch the skin and use a 45-degree angle if you're lean.
  • Reusing syringes — insulin syringes are single-use. The needle dulls and is no longer sterile.
  • Injecting too close to the navel — stay at least 5cm away.