Patient education: How to use an autoinjector (The Basics)

What is an autoinjector? — 

This is a device to give medicines as an "injection," or shot.

Most autoinjectors have 1 dose of medicine in them. The needle is hidden by a needle guard. To give the injection, you press the needle guard against the skin. With some autoinjectors, this pushes the needle into the skin and starts the injection. With others, you press the needle guard against your skin and then push a button to give the injection.

Some medicines given by injection come in other devices. These include a needle and syringe or a "pen injector." A pen injector might look similar to an autoinjector, but the steps for how to use them are different.

This information is about autoinjectors only. Make sure that you know which type of injection device you have and read the instructions that come with it. Check with your doctor, nurse, or pharmacist if you have any questions about your device or how to use it.

What kinds of medicines can be given with an autoinjector? — 

Many different medicines can be given with an autoinjector. Examples include medicines to:

●Treat conditions like:

•Obesity

•Arthritis

•Asthma

•Hormone deficiency

•Crohn disease

•Ulcerative colitis

•Psoriasis

•Diabetes

•Migraine

•Multiple sclerosis

•High cholesterol

•Lupus

•Low white blood cells from chemotherapy

●Help in an emergency, like if you have a serious allergic reaction (called "anaphylaxis") or severe low blood sugar (called "hypoglycemia")

What are the parts of an autoinjector? — 

There are many types of autoinjectors. Look at the instructions that come with yours. Most autoinjectors have these parts (figure 1):

●One or more safety caps – These might protect the needle guard or the button that gives the shot.

●A needle guard or cover – This goes over the area where the needle comes out.

●A viewing window to make sure that the shot was given – This might change colors after you give a shot.

Some autoinjectors have a button to give the shot. Most autoinjectors are used once and then thrown away. Some have a single-dose cartridge that can be replaced. For these, the autoinjector is reused, and each cartridge comes with a new needle.

Where do I inject the medicine? — 

This depends on your medicine and the type of injection device you have. In most cases, you can give the shot in your belly, upper arms, or thighs (figure 2). Change where you give yourself the shot each time. This helps avoid soreness, skin thickening, and fat deposits.

Do not inject medicine into moles, scars, or stretch marks. Avoid areas that are open, bruised, red, hard, or tender. Do not inject medicine within 2 inches of your belly button.

How do I use an autoinjector? — 

Ask your doctor, nurse, or pharmacist if you have any questions about your medicine. In general, these are the steps to using an autoinjector.

●Check the medicine:

•Read the label to make sure that you have the correct medicine and the correct dose. Make sure that you are using the correct concentration.

•Check that the medicine is not expired.

•Know how long you are supposed to use the medicine and how to use it.

•Know how to store the medicine. Some medicines must be stored in the refrigerator.

●Wash your hands with warm, soapy water before you begin and after you are finished.

●Gather your supplies. This includes the autoinjector and alcohol wipes. You might also need a new cartridge of medicine. If the medicine is stored in a refrigerator, you might need to let the cartridge or autoinjector sit at room temperature for 15 to 45 minutes before using it.

●Get the autoinjector ready:

•Take the device out of the case. If needed, insert the medicine cartridge into the autoinjector.

•Hold the autoinjector in your hand. Make sure that your fingers aren't covering either end.

•Take off the safety cap (or caps). Sometimes, when the cap is removed from the needle, a few drops of liquid might come out. This is OK.

●Give the shot (figure 3):

•Clean the skin where you plan to give the shot with an alcohol wipe. Let the skin dry fully. The alcohol helps prevent infection.

•In some cases, you will pinch the skin where the medicine is injected. This keeps the medicine from going into the muscle, where it is absorbed more slowly. To do this, pinch 1 to 2 inches (2.5 to 5 cm) of skin between your fingers and thumb on 1 hand. In other cases, you stretch the skin between your fingers. Make sure that you know whether or not you need to pinch or stretch the skin.

•Firmly press the autoinjector straight down against the skin. Autoinjectors work in 1 of 2 ways:

-The injection starts when the needle guard is pressed firmly against the skin.

-Pushing a button starts the injection after the needle guard is pressed firmly against the skin.

•Keep pressing the autoinjector into the skin for as long as it says in the instructions for your device, usually 5 to 15 seconds. This makes sure that you get the full dose of medicine.

•You might hear several clicks as the medicine is being injected. Some autoinjectors have a viewing window that changes color as the medicine is injected.

•Let go of the skin, and pull the autoinjector straight away from the skin. The needle guard will cover the needle. If you see blood or clear fluid when you remove the needle, press on the area for about 5 seconds. Do not rub.

●Throw away the used autoinjector in a "sharps container." This is a special container made of thick plastic.

What are the risks of using an autoinjector? — 

Your doctor, nurse, or pharmacist will talk to you about all of the possible risks and answer your questions. Possible risks include:

●Pain

●Infection

●Not getting the correct dose of medicine

What else should I know?

●Do not inject medicine through clothes, unless you were told to. Some medicines used for emergencies can be injected through clothing to help give the dose more quickly.

●If you have trouble seeing or hearing, you might need help to use your injection device.

●Some medicines are clear and colorless or clear, pale yellow in color. Others are cloudy. Make sure that you know what your medicine should look like before using it. If your medicine does not look the way it should, do not use it.

●Some medicines must be mixed by shaking the autoinjector before use. Make sure that you know if you need to shake the autoinjector first.

●You might see a small air bubble in the viewing window. This is OK. You do not need to remove it.

●Once the safety cap (or caps) is removed, it usually cannot be put back on. Wait to remove the cap until you are ready to give the injection.

●Firmly hold the autoinjector against the skin for the full time that the instructions say. If you pull the autoinjector away too soon (for some devices this is before the viewing window completely changes color), you will not get the full dose of medicine.

●If you don't have a sharps container, you can use a heavy-duty plastic household container with a tight-fitting lid, such as a laundry detergent container, instead. Always follow local rules for disposing of the sharps container when it is full.

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