When insulin is to be administered subcutaneously by injection, the injection site should be clean and the person giving the insulin should wash their hands.

In the UK, 4-6mm sized needles tend to be used most commonly.

Prior to each administration, usual advice is to draw up insulin or dial up the dose using an insulin pen. The user is then asked to perform an 'air shot'. This is where 2-3 units are discharged into the air to ensure that the syringe or insulin pen are working correctly.

Provided that this demonstrates insulin release, the required treatment dose can then be drawn or dialled up.

The appropriate injection site is then chosen.