How to Prepare for Your First Insulin Injection
, by Andrew Odgers, 11 min reading time
First Injection
How to Prepare for Your First Insulin Injection
Starting insulin can feel daunting. With the right preparation and training, most people find that insulin injection is straightforward and quickly becomes a routine part of daily life. This guide walks through everything you need to know and do before your first injection at home, and covers the step-by-step process from insulin check to disposal.
Before your first injection
What to arrange and understand before you begin
Training with your diabetes nurse
Your diabetes nurse or diabetes specialist nurse will train you on insulin injection technique before you administer your first dose at home. This training covers how to handle and prime your pen device, how to dial the correct dose, how to inject, and what to observe after injection. Do not attempt your first insulin injection at home without this training. The technique is not complicated but it is important to have it demonstrated and to practise it in a supervised setting before doing it alone.
Understanding your insulin and pen device
Before your first injection, you should know: the name and concentration of your insulin, the maximum dose your pen can deliver in one injection, how to read the dose window on your pen, how to prime the pen needle, and how to recognise when the cartridge is running low. Your diabetes nurse will cover all of this during your training. Read the pen device instructions as well as the insulin product information leaflet and keep both accessible at home.
What you need before you inject
For each injection you need: your insulin pen loaded with the correct insulin cartridge, a fresh pen needle of the correct gauge and length for your pen and your anatomy, a clean surface to work on, and a sharps bin within reach for immediate needle disposal. You do not need an alcohol swab for routine home insulin injections in a clean environment, though if you prefer to use one, allow it to dry completely before injecting.
Step by step
Your first insulin injection from preparation to disposal
Step 1: check the insulin
Check the insulin name and concentration on the cartridge against your prescription. Inspect the insulin: it should be clear and colourless for rapid-acting and long-acting analogues, or uniformly cloudy white after mixing for premixed or NPH insulins. Do not use insulin that is discoloured, contains particles, or has passed its expiry date. If the pen has been in the fridge, allow it to reach room temperature for 20 to 30 minutes before injecting.
Step 2: attach a fresh needle
Remove the paper tab from a fresh pen needle and screw or click it onto the pen according to the needle manufacturer's instructions. Remove the outer needle cap and keep it for safe removal after the injection. Remove the inner needle cap and discard it.
Step 3: prime the pen
With a new pen needle attached, point the pen upward and dial two units. Press the plunger until a drop of insulin appears at the needle tip. This confirms the needle is clear and removes any air bubble from the cartridge tip. If no drop appears, repeat the prime. Do this prime check before the first injection from each new cartridge.
Step 4: dial your dose
Dial the prescribed dose using the pen's dose selector. Confirm the number in the dose window matches your prescribed dose before injecting.
Step 5: choose and prepare the injection site
Choose a clean, healthy area within your approved injection sites: the outer upper arm, the abdomen excluding the navel area, the outer thigh, or the upper outer buttock. Inspect the site for lumps, bruising, or recent injection marks and move to a fresh area if any are present. Most adults injecting with a 4 to 6 mm needle do not need a skin fold. If your nurse has advised a skin fold, pinch gently with two fingers before inserting.
Step 6: inject and hold
Insert the needle at 90 degrees to the skin in a smooth, confident motion. Press the plunger fully until the dose counter reaches zero. Hold the needle in place for a count of ten seconds before withdrawing. Release any skin fold after the plunger is fully depressed and before withdrawing.
Step 7: remove the needle and dispose
Withdraw the needle in the same direction as insertion. Replace the outer needle cap using the cap shield without holding the cap in your other hand, or remove the needle directly into the sharps bin without recapping. Dispose of the needle immediately after each injection. Never leave a needle attached to the pen between injections.
Everything you need to start
Insulin pen needles for first-time and experienced users alike
Charles Medical supplies insulin pen needles in fine gauges and short lengths suited to all common pen devices. Next-day UK delivery with no minimum order.
For a full guide to the errors that most commonly develop after starting insulin, see Common Mistakes When Using Insulin Needles and How to Avoid Them.
Part of the hub
Back to the Insulin Needles Knowledge Hub
This article is part of our complete insulin needle knowledge base, covering injection technique, needle selection, pain reduction, site care, disposal, travel, and everything patients managing insulin at home need to know.
Keep reading
Related guides in this hub
What Are Insulin Needles and How Do They Work covers the device and its design for those who want to understand what they are using. How to Know If You Are Injecting Insulin Correctly helps you evaluate your technique as you gain experience. And How to Reduce Pain During Insulin Injections covers what to do if injections are more uncomfortable than expected.
Frequently asked
First insulin injection questions answered
Do I need to swab the skin with alcohol before injecting?
Current UK diabetes nursing guidance does not routinely recommend alcohol swabbing before insulin injection in a clean home environment. If you prefer to use a swab, allow the alcohol to dry completely for at least 30 seconds before inserting the needle. Injecting through wet alcohol causes a stinging sensation that is easily avoided by waiting for full drying.
How do I know if the pen is primed correctly?
After attaching a fresh needle and dialling two units, press the plunger until a small drop of insulin appears at the needle tip. The drop confirms the needle is clear and the cartridge-to-needle path contains insulin rather than air. If no drop appears after two attempts, contact your diabetes nurse or check the pen instructions.
What if I cannot reach my injection site comfortably?
The thigh is usually the most accessible site for self-injection if you have difficulty reaching the abdomen or upper arm. Your diabetes nurse can advise on which sites are most suitable for your physical situation and whether any technique adaptations are needed. Do not inject into sites you cannot see or assess clearly.
What should I do if I accidentally inject twice the dose?
Contact your diabetes team or NHS 111 immediately. Do not wait to see what happens. Tell them the insulin name, the intended dose, and the dose actually given. Eat a carbohydrate snack if you are able to, check your blood glucose, and follow the advice you are given. This is a situation where prompt contact with your diabetes team is essential.