How to Inject Properly: Subcutaneous Self-Injection Step by Step

**A clean subcutaneous self-injection has six steps: wash hands, inspect the vial, wipe the site with a 70% alcohol pad and let it dry, lift a skin pinch if you are lean, stick fast at 90° with a 30G × 6 mm needle, inject slowly counting to five, then count two before pulling out.** Drop the used syringe straight into a sharps container — do not recap it. Rotate sites by at least 2 cm each time. That is the entire technique; everything else is troubleshooting.

This guide is for the moment something weird happens. Most self-injection guides read like they were translated from a hospital pamphlet — you memorise five steps, stand in your bathroom at 8am, and then a drop of blood appears, a bruise forms, or a sting feels wrong, and you are searching for answers at 8:03am. Below is what we wish those pamphlets had said.

## Before you even open the box

The most common reason injections go sideways is not technique. It is a box of pads sitting on the bathroom shelf for six months with the foil pouches half-open, or a vial left on the counter overnight, or a syringe whose packaging has a pinhole you did not notice.

Two habits that solve 90% of this:

1. **Check the pouch before you tear it.** The foil should be taut, not puckered. If you can see the pad is dry or the foil is wrinkled, bin it. A penny's worth of pad is not worth a skin infection.
2. **Look at the vial, not the label.** Particles, cloudiness, colour change, crystals on the stopper — any of these and you are done with that vial. This is not paranoia. Standard pharmacology practice lists visual inspection as step zero.

If you keep supplies in a bathroom, move them. Bathrooms are the worst place to store anything sterile — humidity plus heat swings plus aerosolised soap. A closed drawer in a bedroom is better than the best bathroom cabinet.

## Wash your hands like you mean it

Twenty seconds, warm water, soap, between the fingers, under the nails. Not a rinse, not a splash. This is the single step where the gap between "done properly" and "done quickly" actually shows up as an infection rate.

If you cannot wash, an alcohol hand rub is the fallback — but it is a fallback, not a substitute. Soap mechanically removes dirt. Alcohol does not.

## The pad is not a wipe

The alcohol pad has one job: leave a thin film of 70% isopropyl on the skin and let it dry.

- **70%, not 99%.** Higher is not better. 70% kills more bacteria because the water helps the alcohol penetrate the cell wall.
- **One pad per site, one direction.** Start at the intended injection point and spiral outwards. Do not go back over the same spot.
- **Let it dry.** If you inject while it is still wet, the alcohol stings on the way in and you think you did something wrong. You did not — you just did not wait.

Thirty seconds of drying is plenty. In winter with cold hands, the pad will dry faster than you expect.

## Where to inject — the three usable sites

The three subcutaneous sites that actually work for daily self-injection are the abdomen, the outer thigh and the back of the upper arm. The abdomen absorbs fastest and most predictably, the outer thigh is the easiest one-handed site, and the upper arm is the most awkward to reach but useful for rotation. Stay at least 5 cm from the navel — the tissue there is denser and absorption is uneven.

![Diagram of subcutaneous injection sites — abdomen, outer thigh and back of upper arm with a 5 cm exclusion zone around the navel](/assets/img/blog/diagrams/injection-sites.svg)

## The stick itself

For a 30G × 6 mm subcutaneous injection into belly fat, the textbook says "90° angle, no pinch required" for most adults. Here is what actually works:

- **Pinch if you are lean.** Less than about 6 mm of fat under your fingers and a 90° stick at 30G × 6 mm can scrape against muscle. A light pinch between thumb and forefinger lifts the skin off the muscle layer. You do not need a death grip — just enough to see a small fold.
- **Stick, do not push.** The reason 30G became the self-injection standard is that at that gauge, a confident fast stick goes in cleaner than a slow careful one. A slow stick drags skin. A fast stick pierces it.
- **Aspirate? Short answer, no.** Modern guidance for subcutaneous injections with short needles does not require pulling back the plunger to check for blood. The capillary bed in subcutaneous tissue is low-pressure and the risk of intravenous injection at 6 mm depth in abdominal fat is effectively zero.
- **Inject slowly, count to five.** Then count another two before you pull out. This is the bit that prevents the drop of leakage that makes people think something went wrong.

A good stick should feel like a pinprick and then nothing. A sharp sting *during* the injection usually means either the alcohol did not dry or you found a nerve — pull out, move 1 cm, start over.

## Rotate sites or pay later

This is the one that gets ignored until it stops being ignorable.

Repeated injection in the same 1 cm² patch causes a mild, local buildup of scar tissue (fibrosis) and sometimes lipohypertrophy — a fat-pad thickening that looks like a small lump under the skin. Once it forms, absorption becomes unpredictable at that spot. Stuff you injected yesterday might sit in the lump for hours.

Rotation rules that actually work in practice:

- **Keep a map.** You do not need an app. A simple mental grid: upper-left belly, upper-right belly, lower-left belly, lower-right belly, outer thighs (left, right). Six sites. One per day, rotating.
- **At least 2 cm from the last site.** A finger-width apart is enough. You are not trying to use every square centimetre of abdomen — you are trying to never hit the exact same spot twice in a week.
- **Avoid scars, moles, and the area within 5 cm of your navel.** The tissue around the navel is denser and absorption there is uneven.

## What about bruising

Small bruises are normal and mean nothing. You nicked a tiny capillary on the way in. They usually fade in three to five days.

A bruise that spreads beyond a £1 coin, a hot red patch, or pain that gets worse over 24 hours is different — that is not a bruising concern, that is a "stop and contact a medical professional" concern.

## Disposal is part of the technique

Used syringes go in a proper sharps container, full stop. A screw-top bottle (a rigid plastic detergent bottle works fine) is an acceptable short-term container. Glass, cardboard, or a soda can are not. In most EU countries you can drop a full sharps container off at any pharmacy — they take them. UK home users can usually request collection through their local council.

Never recap a needle. The single most common needlestick injury in home users comes from trying to put the cap back on.

## The shortlist

- Soap handwash. 20 seconds.
- Check the vial and the pad's foil before you open either.
- One pad, one direction, let it dry.
- Pinch if you are lean. Stick fast. Inject slow.
- Count five, wait two, pull out.
- Rotate. 2 cm minimum. Keep a rough mental map.
- Sharps go in a container, caps stay off.

That is the entire technique. Every extra ritual you have been taught beyond this is probably noise.

## FAQ

**Do I need to aspirate before a subcutaneous injection?**
No. Current UK and EU diabetes society guidance does not require aspiration for subcutaneous injection with short needles. Short-needle technique into abdominal fat does not reach a vein.

**Should I pinch the skin before injecting?**
Pinch if you are lean enough that a 6 mm needle could reach muscle — fewer than 6 mm of subcutaneous fat under your fingers is the rough threshold. Most adults of average build do not need to pinch with a 4 mm or 6 mm needle.

**What angle do I inject at?**
90° for most adults using a 4–6 mm needle. 45° if you are very lean and pinching, or using an 8 mm needle.

**How do I know I picked a good injection site?**
At least 2 cm from the last site, avoiding scars, moles, and the area within 5 cm of the navel. Rotate through six rough zones — four abdomen, two outer thighs.

**Why does a tiny drop of liquid sometimes appear after I pull the needle out?**
You pulled out before the tissue closed around the track. Counting two seconds after the plunger bottoms out before withdrawal usually fixes it. A drop is not a lost dose worth redosing for.

**What do I do with the used syringe?**
Straight into a sharps container, no recapping. UK users can request council collection; EU users can drop the sealed container at a pharmacy.

If you are restocking after the first month, the [30G × 6 mm insulin syringe range](https://30-g.com/products) plus alcohol prep pads and a 1 L sharps container is the standard kit — that is what we ship in the starter bundle.

_This article is for general information only and is not medical advice. Always consult your prescriber or pharmacist for guidance specific to your situation._