For people with diabetes, insulin injections deliver the drug to the subcutaneous tissue (the tissue between the skin and muscle), which is present throughout the body.
Follow these steps to inject insulin using a syringe; note that these instructions do not apply to insulin pens or non-needle injection systems.
Prep
Select a clean, dry work area and prepare the following supplies for insulin injection:
- A bottle of insulin;
- A sterile insulin syringe (with needle attached) with packaging removed;
- Two alcohol wipes, or cotton balls and a bottle of alcohol.
For containers to store used devices, consider rigid plastic or metal containers with screw-on or snap-on lids, or buy “sharps-only” boxes from the market.
Wash your hands with soap and warm water, and dry them with a clean towel.
Prepare insulin and syringes
Remove the plastic cap from the insulin bottle.
Roll the insulin bottle 2 to 3 times between your hands to mix the insulin; do not shake the bottle, as shaking may form air bubbles and affect the amount of insulin drawn.
Wipe the rubbery part of the top of the insulin bottle with an alcohol tablet or cotton ball soaked in alcohol.
Place the insulin bottle on a flat surface.
Remove the cap from the needle. If you need to use two types of insulin at once (mixed doses), skip to the instructions in the next section.
Injection procedure
Pull back on the plunger to draw air into the syringe. The amount of air drawn into the syringe should be the same as the amount of insulin to be injected, always measured from the top of the plunger.
Insert the needle into the rubber stopper of the insulin bottle and push down on the plunger to inject air into the bottle so that it is easier to draw in insulin, leaving the needle in the bottle.
Invert the bottle and syringe, making sure the insulin solution covers the needle.
Pull the plunger back to the desired insulin dose, measuring from the top of the plunger.
Check for air bubbles in the syringe
Check for air bubbles in the syringe. Air bubbles in the syringe are not harmful, but will reduce the insulin dose in the syringe. Remove the air bubbles by gently tapping the syringe so that the bubbles rise to the top and pushing up on the plunger to remove the bubbles.
If necessary, recheck the dose and add more insulin to the syringe.
Pull the needle from the insulin vial and carefully close the cap on the needle.
How do I aspirate mixed insulin?
Your doctor may order two types of insulin to treat your diabetes, and this mixed dose may provide better blood glucose control for some patients.
To inject a mixed dose of insulin, follow these steps.
Medium-acting or long-acting insulin
Prepare two vials of insulin according to the steps above.
Pull back on the plunger to draw air into the syringe. The amount of air drawn into the syringe is equal to the amount of cloudy (medium- or long-acting insulin is a cloudy liquid) insulin required, always measured from the top of the plunger (closest to the edge of the needle).
Insert the needle into the rubber stopper of the insulin bottle and push the plunger down to inject air into the bottle so that the insulin can be more easily aspirated; do not aspirate the insulin into the syringe at this time and pull the needle out of the bottle.
Short-acting insulin
Pull back on the plunger to draw air into the syringe. The amount of air drawn into the syringe is equal to the amount of clear (short-acting insulin is a clear solution) insulin needed, always measured from the top of the plunger.
Insert the needle into the rubber stopper of the clear insulin bottle and push the plunger down to inject air into the bottle , which makes it easier to draw insulin.
Invert the bottle and syringe, making sure the insulin solution covers the needle.
Pull the plunger back to the desired clear insulin dose, measuring from the top of the plunger, closest to the edge of the needle.
Check the syringe for air bubbles
Air bubbles in the syringe are not harmful but can reduce the insulin dose in the syringe. Remove the bubbles by gently tapping the syringe so that the bubbles rise to the top and pushing up on the plunger to remove the bubbles and, if necessary, recheck the insulin dose and add more insulin to the syringe.
Remove the needle from the clear insulin vial and insert it into the rubber stopper of the cloudy insulin vial.
Invert the bottle and syringe, making sure the insulin solution covers the needle.
Pull back the plunger to the desired total insulin dose, measuring from the top of the plunger.
Important tips
It is important to ensure accurate measurement, and if too much cloudy insulin is drawn, the entire insulin in the syringe must be discarded, being careful not to push any clear insulin from the syringe into the cloudy insulin bottle.
If there are large air bubbles after mixing insulin in the syringe, discard this dose and re-do the procedure without pushing the insulin back into the bottle.
Carefully put the cap back on the needle.
Now that you are ready to inject insulin, follow these steps.
Rotate insulin injection sites
People with diabetes need regular insulin injections. Knowing where to inject and how to change injection sites makes it easier, safer, and more comfortable to inject insulin by rotating injection sites.
If you inject at the same site repeatedly, you may develop hardened areas under the skin that can prevent insulin from being used properly.
Important: Only choose the front part of the body when injecting insulin yourself; if someone else is injecting for the patient, choose any part.
Follow these guidelines
Consult your doctor, nurse, or health educator about where you should inject yourself.
Each time you change injection sites, inject at least 4 cm from the nearest injection site.
Try to use the same injection area at the same time each day, for example, use your abdomen before lunch, noting that the abdomen absorbs insulin fastest, followed by your arms, thighs, and buttocks.
Record the injection sites you have used.
Select the injection site and sterilize it
Select the site for insulin injections.
Do not inject in the joints, groin, umbilicus, middle of the abdomen, or near a scar.
Clean the injection site (approximately 5 cm diameter of skin) in a circular motion using an alcohol swab or cotton ball moistened with alcohol, leaving the alcohol swab or cotton ball in a nearby location.
Injecting insulin
Hold the syringe barrel of the syringe in a pen-holding position with the writing hand, with the needle pointing inward, being careful not to place your finger on the plunger.
Remove the cap from the needle.
Gently pinch the skin 5 to 8 cm on either side of the sterilized injection site with the other hand.
Insert the needle at a 90-degree angle (straight up and down) into the pinched skin quickly, with the needle fully inside the skin.
Push the plunger of the syringe until all the insulin has been pushed out.
Pull out the needle quickly and do not wipe the injection site, which may or may not bleed after the injection; if it is bleeding, apply light pressure with an alcohol cotton ball and cover the injection site with a bandage if necessary.
Handle the syringe and needle
Do not put the cap on the needle, put the entire syringe and needle in the “sharps” box, and when the box is full, put the cap on and throw it away.
Do not put the container in the trash, consult your local health department for disposal.