Insulin

Insulin pens – how to inject insulin

It is important to inject insulin correctly. Ask your diabetes nurse, pharmacist or doctor for advice. The following information is a guide.

Priming your insulin pen

Priming your insulin pen means removing any air from inside the insulin cartridge, to ensure you get an accurate dose. It also ensures your pen is working correctly. It is important to prime your insulin pen with at least 2 units of insulin before every injection. 

• To prime your pen, use the dose selector knob to dial 2 units.
• Hold your pen with the needle pointing up, into the air. 
• Tap the cartridge gently to collect air bubbles at the top.  
• Push the dose selector knob until it stops and zero is seen in the dose window. Hold this for a few seconds.
• You will see drops of insulin at the tip of the needle. 
• If you do not see insulin drops, then repeat the process, or change the needle and repeat the priming steps.
• Note: tiny air bubbles are normal and will not affect your dose.      

If 2 units are used for priming each injection, this can add up to between 1–3 additional 3mL cartridges in 3 months. Tell your doctor to prescribe enough insulin to allow for priming with each injection.

Selecting your dose

• Wash your hands with soap and water before injecting.
• Use a new needle for every injection to minimise pain. Reusing needles can lead to bruising, bleeding and infection.
• Dial the number of units you are going to inject by turning the dose selector knob.   
• Inject insulin into the fatty tissue just under your skin, in the abdomen or tummy area, about 5 cm away from your belly button. Read more about injection sites below.
• Hold the pen in your hand with your thumb or finger on the dose selector knob at the end of the pen.
• If you are using an 8 mm (or longer) needle, pinch up your skin on your stomach then slide the needle into the skin fold at a 90º angle. If your needle is less than 8 mm long, don't pinch up your skin.   
• Push the dose selector to inject the dose, relatively slowly, as far as it will go. The dose window should read zero. 
• Leave the needle in for 6 seconds.
• Continue to push in the dose selector knob while you remove the needle.

Storing your insulin pen

• Insulin pens that you are currently using are not kept in the fridge.
• Spare pens can be kept in the fridge but once they are in use, and have a needle attached, they should be kept out of the fridge.
• If they remain in the fridge, insulin can leak out. Also, pens that are frequently moved in and out of the fridge can accumulate air bubbles.

Tips to minimise pain when injecting insulin

Injecting insulin can cause discomfort, but it should not be painful. Here are a few tips to minimise pain when injecting:

• Make sure your stomach muscles are relaxed.
• Use insulin and a needle at room temperature.
• Push the needle in quickly and hold for about 10 seconds before removing the needle.
• Try not to wiggle the needle as you’re injecting or removing it.
• Always use a new needle for every injection. 
• Move the site of injection – do not inject into the same site you last used. This will help avoid scarring and reduce pain. 

Learn more

The following links provide more information on injecting insulin. Be aware that websites from other countries may have information that differs from New Zealand recommendations.

How to inject insulin Diabetes.co.uk, UK
Injecting insulin for type 1 diabetes NPS MedicineWise, Australia)

References

1. Insulin prescribing SafeRx Waitematā DHB, NZ, 2017
2. Insulin injection know-how American Association of Diabetes Educators, US