How to: Intramuscular injection

How to inject testosterone via intramuscular route:

Testosterone should only be injected if it has been prescribed by a medical doctor.

Let’s review the safest way to inject testosterone medications. You can also watch a video tutorial on this link.

What is an intramuscular injection? 

An intramuscular (IM) injection delivers medication deep into the muscle tissue. This allows the medication to be quickly absorbed into the bloodstream. Intramuscular shots are given at a 90- degree angle. The needle for IM injections can be 25 Gauge, 1-1.5 inches in length, adjusted for thickness of site. 


Step 1: Find a comfortable, well-lit working place and clean your work area

1. Organize your medications and the equipment you will need for injecting so that you have everything ready in front of you. For example you would typically need:

  • 1 or 2 syringes (1ml)

  • 1 bottle of Testosterone cypionate

  • 1 filter needle (21G)

  • 1 injecting needle (25G, 1 inch length)

  • 1 or 2 alcohol wipes

  • Sharps bin (for disposal of needle)

2. Check the expiration date on the bottle of Testosterone cypionate. Do not use medication with particles, medication that is discolored or has expired.

3. Wash your hands thoroughly with soap, and dry off with paper towel or kitchen roll if possible.

Hand washing is one of the most important things you can do to prevent infection.


Step 2: Where to inject testosterone?

Option 1 (Recommended) – Gluteus Maximus muscle in the buttocks:

We recommend injecting into the glute injection site as it is normally the most comfortable area to inject into, with very little discomfort during and after injecting. It is also one of the safest areas to inject, with a very low likelihood of crossing a vein or nerve.

Where to inject testosterone into buttocks?

You should aim to inject on either buttock at the top corner furthest away from the spine.


Option 2 – Vastus lateralis muscle in the thigh:

This injection site is sometimes slightly more uncomfortable than the Gluteus Maximus to inject into, but some people find it easier to see and administer the injection because it is in front of them rather than to the side/back.

Look at your thigh and divide it horizontally into 3 equal parts. The injection will go in outer middle third.

Form a V with your fingers by separating your first finger from the other 3 fingers. Place the heel of your hand on the bone (femur) that ends before the knee bends and aim the injection right above the V in the center of the thigh.

Step 3: Preparing the Injection Dose

  1. Check the packaging of the syringes and needles you are going to use. If the packaging has been opened or damaged, do not use those syringes or needles.

  2. Prepare the vial. If this is a new vial, take the cap off. Clean the rubber stopper with one alcohol swab. Allow to dry. 

  3. Open the syringe package carefully, taking care not to touch the open end of the syringe against anything, including your hands.

  4. Open the 21G needle package carefully, taking care not to touch the open end of the needle against anything, including your hands. Screw the 21G needle onto the end of the syringe. Your syringe may come with an 21G needle attached (you’re ready to go). 

  5. Pull the 21G needle cover straight off the needle. Then, pull back the plunger and draw air into the syringe. The amount of air drawn into the syringe should be the same amount (mL or cc) as the dose that your doctor prescribed.

  6. Do not let the needle touch any surfaces.

  7. Keep the vial on your flat working surface and insert the needle straight down through the center of the rubber stopper. Do not put the needle through the rubber stopper more than once. 

  8. Push the plunger of the syringe down and push the air from the syringe into the vial. 

  9. Keeping the needle in the vial, turn the vial upside down. Position the needle so the liquid is covering the tip of the needle. 

  10. Keeping the vial upside down, slowly pull back on the plunger to fill the syringe with the medication to the number (mL or cc) that matches the dose your doctor ordered. 

  11. Keeping the needle in the vial, check for air bubbles in the syringe. If there are air bubbles, gently tap the syringe with your fingers until the air bubbles rise to the top of the syringe. Then slowly push the plunger up to force the air bubbles out of the syringe without removing the needle from the bottle. 

  12. After air bubbles are gone, pull the plunger back to the number (mL or cc) marking on the syringe that matches your dose. Remove the 21G needle and replace it with the IM needle (25G).

  13. Check to make sure that you have the correct dose in the syringe. It is very important that you use the exact dose prescribed by your doctor. 

Do not lay they syringe down or let the needle touch anything. 

In this example, the dose in the syringe is 0.3mL.

Step 4: Give the Testosterone Injection

  1. Clean the injection site skin with an alcohol swab; let it air dry.

  2. Gently hold the skin around the injection site so that the skin is slightly taut.

  3. Insert the IM needle into the muscle at a 90 degree angle with one quick and firm motion.

  4. After inserting the needle into the muscle take your hand off the skin.

  5. Gently pull back on the plunger of the syringe to check that blood doesn’t come back into the syringe (this is called ‘aspirating’). If you see blood in the needle/syringe, do not inject the medicine and remove the needle immediately. You must discard the medicine and try again with fresh equipment and medicine if blood does come up the needle into the syringe when you aspirate.

  6. If you do not see any blood in the needle, you can complete the injection by pushing the medication slowly into the muscle. You may feel some mild pressure as the medicine enters your muscle.

  7. When you finish injecting the full dose of the medication into the muscle, remove the needle slowly and at the same right angle that you inserted the needle. Sometimes you might see a small drop of blood at the injection site, this is normal and nothing to be alarmed about.

  8. Gently press an alcohol swab on the testosterone injection site. Hold pressure on site until there is no bleeding. You can place a band aid/plaster on the injection site if needed.

Tips for Reducing Testosterone Injection Pain

  • Inject medicine that is at room temperature.

  • Remove all air bubbles from the syringe before injection.

  • Let the skin dry after using alcohol wipes before injecting.

  • Keep the muscles in the Testosterone injection area relaxed.

  • Break through the skin quickly with the needle.

  • Don’t change the direction of the needle as it goes in or comes out.

  • Do not reuse disposable needles.

Instructions for Disposing of 'Sharps':

Improper disposal of syringes and other sharp objects can pose a health risk and damage the environment.

Please always dispose of your used syringes and needles using a sharps bin.

The sharps box should then be disposed of in line with the following FDA guidelines: https://www.fda.gov/medical-devices/safely-using-sharps-needles-and-syringes-home-work-and-travel/dos-and-donts-proper-sharps-disposal