Diabetes: Drawing Up and Giving Insulin
Learning to draw up and give insulin takes practice. Families often start by doing "air" shots into a doll for practice. Next they practice drawing up sterile salt water (saline) and injecting each other. This helps family members realize that the shot is not very painful. Children below age 10 usually do not draw up insulin by themselves as they do not have the fine motor abilities and concern for accuracy. Your child will need your help.
What kind of syringe should we use?
There are now several brands of disposable insulin syringes with varying needle widths. Needle thickness is measured in gauges. A larger number means it has a thinner needle (for example, a 30 gauge needle is a thin needle). Needles also come in varying lengths. The standard length is 1/2 inch. Insulin syringes should have thin, short, sharp needles so they are easy to insert.
The amount of insulin a syringe will hold varies. Insulin is measured in units. Example of common syringes:
- 3/10cc (holds 30 units)
- 1/2cc (holds 50 units)
- 1cc (holds 100 units)
Syringes have markings on the side that measure the units. A 3/10cc syringe has a larger distance between the unit lines and is easier to use if you need to measure small doses. There are even some syringes that have markings for half units. If you do not want to throw away the syringe after each use, you can reuse it. However, the needle may get dulled from going through the rubber stopper on the insulin bottle over and over. A dull needle may cause more damage to your child's skin and tissues. There is also a possibility of infection when reusing syringes.
How do I draw up the insulin into the syringe?
Your healthcare provider will show you how to draw the insulin into the syringe.
These are the steps:
- Get your supplies (syringe, insulin, alcohol) and wash your hands.
- Push the plunger of the disposable syringe up and down before drawing in the insulin. This will help soften the rubber at the end of the plunger and smooth the plunger action.
- Wipe the top of all the insulin bottles you are going to use with alcohol and allow to air dry.
- Add air to the bottles (unless you are venting the bottles once a week). Use the syringe to push the same amount of air into the bottle as insulin you are planning to use (for example, if you are going to use 20 units of insulin, then inject 20 units of air into the bottle). If you are taking more than one type of insulin, add air to the intermediate-acting insulin bottle first and then to the rapid-acting insulin bottle. After adding air to the rapid-acting insulin bottle, leave the needle in the bottle.
- Turn the rapid-acting insulin bottle (with the needle inserted) upside down. To remove any air bubbles, draw out about 5 units of insulin and then push the bubble and the 5 units back into the bottle. This can be repeated several times as needed until air bubbles are cleared. "Flicking" the syringe barrel with the finger is not recommended as it can cause the needle to bend.
- After the air bubbles are gone, adjust the top edge of the rubber plunger to be in line with the exact number of units needed.
- Remove the syringe from the bottle and hold it in your hand.
Continue with steps 8 and 9 if you need to add an intermediate-acting insulin to the same syringe. If you want to have both hands free, you can leave the syringe stuck in the rapid-acting insulin bottle until you have mixed the intermediate-acting insulin.
- Mix the intermediate-acting insulin by turning the bottle back and forth or rolling it between the palms of your hands 20 times. Avoid touching the rubber top that you cleaned with alcohol.
- Turn the bottle upside-down and then insert the syringe into the bottle. (Turning the bottle upside-down prevents air from the bottle getting into the syringe.) Slowly draw the number of units of the intermediate-acting insulin needed. The total number of units in the syringe will be the sum of the rapid-acting units plus the intermediate-acting units.
How do I vent the insulin bottle?
One problem with insulin bottles is that a vacuum can develop which will draw the insulin in the syringe back into the bottle. To avoid this problem, you can do one of two things:
- Inject air into the insulin bottle before each dose (as described above)
- Vent the bottles once per week.
Venting the bottles
To vent the bottles:
- Remove the plunger from a syringe barrel.
- With the insulin vial sitting upright on the table, insert the needle into the rubber stopper and allow the air to equalize in the insulin bottle. This will quickly remove any vacuum which may be inside the bottle.
Pick one consistent day of the week to vent the bottles.
When should I give the insulin?
The rapid-acting insulins (Humalog, NovoLog, Apidra) peak in 90 to 100 minutes. The blood sugar from food peaks in 60 minutes. It is best to inject the insulin 15 to 30 minutes before eating, if the blood sugar is above 80 mg/dl (4.4 mmol/L). If the blood sugar is below that level, the insulin dose can be given right before or right after eating.
Where should I inject the insulin?
Insulin is injected into the fat layer beneath the skin. The best places to give insulin are the abdomen, arms, thighs, and buttocks. You should rotate injection sites. If your child doesn't like to have shots in one of these areas, then you should rotate the shots between the other areas and skip the area that bothers your child. Shots should not only be rotated from site to site but also within the site itself. For example, there might be 6 different places on the thigh that you can use. This way your child can have a shot in over 50 different spots, before having to have a shot in the same place again. For example, see injection rotation chart.
- Insulin should NOT be injected just before a bath, shower, or hot tub. The warm water will draw more blood to the skin, causing the insulin to be absorbed quickly. This can cause a serious low blood sugar reaction.
- Do not give a shot into an area that is swollen.
- Insulin is absorbed more rapidly from the abdomen than from the arm, and more rapidly from the arm than from the thigh or buttock. This difference is not noticeable for most people. If you do notice a difference, you may want to use one site for morning shots and another site for dinner shots. For example, the abdomen or arm might be used in the morning. The thigh or buttock might be used in the evening. Rotating injection sites helps prevent swelling. Lantus or Levemir insulin must be injected into fat to be effective. The buttocks are usually the best place to inject either of these insulins.
- Insulin is absorbed quicker if it is given in an area that is then exercised. Giving insulin into an arm or leg which will be used during exercise may result in low blood sugars during exercise. For example, if your child is going to play tennis, don't give a shot into the arm that will be used to swing the racquet.
- Put colored tape around the vial of Lantus or Levemir insulin. This can help you tell these insulins apart from Humalog, NovoLog, or Apidra insulins.
How do I inject the insulin?
It is important to learn the proper technique. If you give the shot too close to the outer skin it can cause a lump, pain, or a red spot. If you give the shot too deep into the muscle it may be more painful and cause the insulin to be absorbed too quickly. You want to avoid injecting insulin into a large vein or artery. This is very unlikely if you are giving shots in the recommended areas. If you did inject insulin into a large vein or artery, the insulin would last only a matter of minutes rather than hours. Do not worry about accidentally injecting a bubble of air into your child (even into an artery or vein). It will not harm your child.
To inject the insulin:
- Clean the area with soap and water. Alcohol dries and toughens the skin, so don't use it everyday for cleaning the area. Alcohol wipes are great for camping or when you do not have water nearby.
- Lift up the skin with a gentle pinch.
- Touch the needle to the skin and gently push it through the skin. Use a 45° angle for the 1/2 or 5/8 inch long needle or a 90° angle for the 5/16 inch (short) needle.
- With the plunger, push the insulin in SLOWLY and steadily.
- After all the insulin is in wait 5 to 10 seconds before removing the needle. This will help prevent insulin leakage from the injection site. Loss of insulin is a common reason for variations in the blood sugar levels.
- Put a finger or dry cotton over the site as the needle is pulled out. Gently rub the area a few times. This helps close the track left by the needle.
How do I store the insulin?
Ideally, insulin should be stored in the refrigerator and warmed to room temperature before using. You can warm it up by holding your filled syringe between your hands for a minute or two. If you warm the insulin to room temperature, it is less likely to sting or cause red spots on the skin.
Some people store the bottles they are using at room temperature (except during very hot summer months). Research has shown that insulin stored at room temperature loses a small percentage of its potency every month. For most people, this small change will not make a difference. Watch your child's blood sugar levels carefully when the insulin bottle is almost empty. If the blood sugars start to be unusually high or low, the last bit of insulin should be thrown out.
Insulin will spoil if it gets above 90°F (32.2°C) or if it freezes. Insulin bottles (or pens) should not be left in a car in the hot summer or the cold winter.
Throw away insulin if:
- clumps are sticking to the side of the bottle (intermediate-acting insulin)
- the clear, rapid-acting insulin becomes cloudy
- it is past the expiration date
- the bottle has been stored at room temperature and has been open for over 30 days
- the bottle has been stored in the refrigerator and has been open for 3 or more months.
The plastic syringes are recommended for one time use only. If you need to reuse the syringe, after giving the injection, push the plunger up and down to get rid of any insulin left in the needle. Wipe the needle off with an alcohol swab. Put the cap over the needle and store the syringe and needle in the refrigerator until ready for the next use.
Abstracted from the book, "Understanding Diabetes," 11th Edition, by H. Peter Chase, MD (available by calling 1-800-695-2873).
Published by RelayHealth.
Last modified: 2010-05-21
Last reviewed: 2010-05-11
This content is reviewed periodically and is subject to change as new health information becomes
available. The information is intended to inform and educate and is not a replacement for medical
evaluation, advice, diagnosis or treatment by a health care professional.