1Belly (abdomen)
Below the ribs and above the hip bones, at least 5 cm (2 in) from the navel. Easy to see and reach, with the most room to rotate.
Stay off the belt line.
Where and how to inject
Peptides measured with insulin syringes and pens usually go into the fat just under the skin (subcutaneous). Here are the usual sites, how to rotate them, which needle and angle to use, and the technique step by step.
4 usual sites5 cm from the navel1 cm between injectionsPens: hold 10 s
Where to inject
Pick a place with a layer of fat you can pinch. Tap an area on the body map to read about it.
2Thighs
The front and outer side of the upper thigh, well above the knee. Easy to reach sitting down.
Lean thighs often need a pinched fold.
3Back of the upper arms
The fleshy back or side of the upper arm, at least 7.5 cm (3 in) below the shoulder and above the elbow.
Hard to reach yourself; easier with help.
4Upper buttocks
The upper outer part of each buttock.
Hard to see: use a mirror or ask for help.
Avoid
- The 5 cm (2 in) around your navel
- Scars and moles
- Bruised, red, swollen, tender or hard skin
- Lumps or thickened spots from earlier injections
Rotate your sites
Injecting into the same spot again and again can build up lumps of hardened fat under the skin, called lipohypertrophy. Lumpy areas absorb unevenly and can hurt, so move every injection.
- Split each area into parts: the belly into four quarters around the navel, the thighs and buttocks into left and right.
- Use one part for a week, then move to the next, always in the same direction.
- Keep each injection at least 1 cm (about a finger’s width) from the last one.
- Feel your sites now and then. If you find a lump, stop using that spot.
- Writing down the site and date helps you keep track.
Needle length and angle
The goal is the fat under the skin, not the muscle. Skin is about 2 mm thick for most adults, so short needles reach the fat easily. Injection-technique experts recommend 4 mm pen needles and 6 mm syringe needles for adults of any size.
Longer needles can go too deep, especially in lean arms and thighs. With them, pinch a fold of skin or go in at 45°.
| Needle | Found on | Angle | Pinch a fold? |
|---|---|---|---|
| 4–5 mm | Pen needles | 90° | No, unless very lean |
| 6 mm | Short insulin syringes, pen needles | 90° | If lean, or on arms and thighs |
| 8 mm | Insulin syringes, pen needles | 90° with a fold, or 45° | Yes |
| 12.7 mm | Standard insulin syringes | 45°, with a fold | Yes. A shorter needle is better. |
The length is on the box, in millimeters or inches: 6 mm is 15/64″, 8 mm is 5/16″ and 12.7 mm is ½″.
How to pinch a fold
Gently lift about 2.5 cm (1 in) of skin and fat between your thumb and index finger, without grabbing the muscle. Insert the needle into the top of the fold and hold the fold until the needle is out.
With an insulin syringe
Draw the number of units the calculator shows for your mix. Use a new syringe every time.
Wash and gather
Wash your hands with soap and water. Set out the vial, a new syringe, alcohol swabs and a sharps container on a clean surface.
Swab the stopper
Wipe the rubber top of the vial with alcohol and let it dry.
Push in air
Pull the plunger back to your dose line, push the needle through the stopper and inject that air into the vial. It makes the liquid easier to draw.
Draw the dose
Turn the vial upside down and draw a little past your dose. Tap any bubbles to the top, then push them back until the plunger sits exactly on your line.
Clean the site
Pick a spot at least 1 cm from the last one. Wipe it with alcohol, from the middle outward, and let it air-dry.
Insert the needle
Hold the syringe like a pencil. Pinch a fold if your needle or the area needs one, then push the needle in quickly and fully, straight in at 90°.
Inject slowly
Press the plunger down steadily until it stops. Keep it there and count slowly to 5.
Withdraw and discard
Pull the needle straight out, then let go of the fold. Don’t rub; press lightly with gauze if it bleeds. Don’t recap the needle: put it straight into the sharps container.
With a peptide pen
Dial the number of clicks the calculator shows for your pen. Use a new pen needle every time.
Wash and wipe
Wash your hands. Wipe the rubber seal at the tip of the pen with alcohol and let it dry.
Attach a new needle
Screw a new pen needle on straight. Pull off the outer cap and keep it, then remove the inner cap.
Prime
Dial the priming clicks set in the calculator, point the needle up, tap the cartridge and press the button until a drop appears.
Dial your dose
Turn the dose knob to your number of clicks and check it in the window.
Clean the site
Pick a spot at least 1 cm from the last one. Wipe it with alcohol, from the middle outward, and let it air-dry.
Press and hold
Insert the needle straight in at 90°. Press the button all the way down and keep it pressed while you count to 10, so the whole dose goes in.
Remove the needle
Pull straight out. Put the outer cap back on the needle, unscrew it and drop it into the sharps container. Cap the pen and put it back in the fridge.
Safety
General technique for subcutaneous injections, summarized from the sources below. It isn’t medical advice: follow your prescriber’s instructions and the leaflet that came with your product.
One needle, one injection
Use a new needle every time and never share needles, syringes or pens. Reused needles are blunter, hurt more and are linked to lumps under the skin.
Sharps container
Put used needles straight into a puncture-proof sharps container, needle first. When it’s full, dispose of it as your local rules require.
Watch the site
Some soreness is normal. See a doctor if you notice spreading redness, swelling, red streaks, warmth or fever.
Emergency
Trouble breathing, swelling of the face, lips or throat, or feeling faint after an injection: call emergency services right away.
Under the skin, not into muscle. This guide covers subcutaneous injection with insulin syringes and pens. Intramuscular injections need longer needles and different sites; ask a clinician to show you.
Sources
- FITTER expert recommendations on injection technique (diaTribe summary)
- BD: injection technique for different needle lengths
- MedlinePlus: giving a subcutaneous injection
- UW Medicine: how to give yourself a subcutaneous injection
- UMass Memorial Health: giving a subcutaneous injection
- Lilly Medical: tips for under-the-skin injection