A subcutaneous (SubQ) injection delivers medication into the fatty tissue layer just beneath the skin. This route is often used for self-administration because absorption into the bloodstream is slower and more sustained. Common medications administered this way include insulin, certain vaccines, fertility drugs, and blood thinners. Understanding the proper technique ensures the medication is delivered safely and effectively at home.
Essential Preparation and Supplies
Before preparing to inject, establish a clean, well-lit work area to minimize contamination and errors. Begin by thoroughly washing your hands with soap and water for at least 20 seconds, then dry them completely. This step prevents introducing bacteria to the injection site or equipment.
Next, carefully inspect the medication and the delivery device, whether it is a traditional syringe or an injection pen. Confirm the medication name, prescribed dose, and the expiration date match your instructions. Check the medication for unusual discoloration or cloudiness, unless it is normally a suspension. Allow refrigerated medications to warm to room temperature for greater comfort during the injection.
Gather all necessary supplies before starting the procedure. These include the medication, a sterile needle and syringe or pen device, alcohol swabs, and gauze. A specific, puncture-proof sharps container designed for the safe disposal of used needles must also be within immediate reach. Organizing all materials prevents fumbling or needing to search for items once the injection process has begun.
Selecting and Preparing the Injection Site
Selecting the correct injection site is important for comfort and proper medication absorption. Common areas with sufficient fatty tissue are the abdomen, the outer upper thigh, and the back of the upper arm. If using the abdomen, choose a spot at least two inches away from the belly button.
Maintaining site rotation prevents localized tissue damage known as lipohypertrophy, which appears as a firm, rubbery lump of fat under the skin. Injecting repeatedly into the same spot impedes consistent medication absorption, making it less predictable and effective. Keeping a log or mental map of previous locations helps ensure the next injection is at least one to two inches away from the last site.
Once a fresh site is selected, prepare the skin using a single-use alcohol swab. Cleanse the area in a circular motion, starting from the center and spiraling outward to remove surface bacteria. Allow the alcohol to completely air dry before injection; injecting through wet alcohol can cause stinging and may carry alcohol into the tissue.
Step-by-Step Subcutaneous Injection Technique
The injection requires precision to ensure the medication reaches the subcutaneous fat layer. Hold the syringe or pen like a dart or pencil in your dominant hand, gently removing the needle cap without touching the sterile needle. With your non-dominant hand, gently pinch a fold of skin and fatty tissue at the prepared site between your thumb and forefinger.
Needle insertion technique depends on the needle length and the amount of fatty tissue present. If using a short needle or if you have significant pinchable tissue, insert the needle quickly at a 90-degree angle straight into the pinched skin fold. If using a longer needle, or if you are lean and can only pinch a small amount of tissue, insert the needle at a 45-degree angle.
Insert the needle in one smooth, quick motion to minimize discomfort, pushing it all the way into the skin fold. Once fully inserted, steady the syringe with your non-dominant hand. Slowly and steadily depress the plunger until all the medication has been delivered.
Keep the needle completely still within the tissue while injecting to avoid damaging surrounding tissue. Some medications, particularly those delivered via an auto-injector pen, require a brief pause after the plunger is fully depressed to ensure the full dose is administered. Follow the manufacturer’s instructions for any specific waiting period.
After the injection is complete, remove the needle quickly and straight out at the same angle it was inserted. Releasing the pinched skin fold as you withdraw the needle helps reduce pulling sensation. Avoid recapping the needle after use to prevent an accidental needlestick injury.
Post-Injection Care and Safe Disposal
Immediately after withdrawing the needle, apply gentle pressure to the injection site using gauze or a cotton ball. If a small drop of blood appears, sustained light pressure for a few seconds will stop the bleeding. Resist the urge to rub the injection site, as rubbing can irritate the tissue or interfere with medication absorption.
The most important safety step following the injection is the immediate and correct disposal of the used needle and syringe or injection pen. These items must never be thrown into regular household trash. Used sharps must be placed directly into a designated sharps disposal container, which is hard plastic, puncture-resistant, and labeled as a biohazard.
Drop the needle into the sharps container without touching the outside or trying to force it in. Once the container is approximately three-quarters full, seal it and dispose of it according to local guidelines. Inspect the injection site over the next few hours for signs of an adverse reaction, such as excessive pain, swelling, or a spreading rash.