TRT Self-Injection Guide — Step-by-Step for Beginners

Subcutaneous vs Intramuscular — Which Is Better?

Most men starting TRT assume intramuscular (IM) is the only option. It's not. Subcutaneous (SubQ) injection has become the preferred method for many clinicians and patients. Here's how they compare:

Factor	Subcutaneous (SubQ)	Intramuscular (IM)
Needle size	27–30 gauge, ½ inch	22–25 gauge, 1–1.5 inch
Pain level	Minimal — like an insulin shot	Moderate — deeper tissue
Injection site	Belly fat, love handles, thigh fat	Glutes, quads, deltoids
Absorption rate	Slower, more steady	Faster initial spike
Hormone stability	More consistent levels	More peaks and troughs
Ease of self-injection	Easy — you can see everything	Harder — glute reach is awkward
Post-injection soreness	Rare	Common (1–2 days)

Supplies You Need

Your provider should ship these with your medication. If you need to source separately:

Supply	SubQ	IM
Drawing needle	18–21g, 1 inch	18–21g, 1 inch
Injection needle	27–30g, ½ inch	22–25g, 1–1.5 inch
Syringe	1mL insulin syringe (or Luer lock)	3mL Luer lock syringe
Alcohol swabs	Yes	Yes
Sharps container	Yes	Yes
Band-aids	Optional	Recommended

Important: Always use a separate drawing needle and injection needle. Drawing through the rubber stopper dulls the needle — injecting with a dull needle hurts more and can cause tissue damage.

Subcutaneous Injection — Step by Step

1. Wash your hands thoroughly with soap and warm water for 20 seconds.
2. Gather supplies: medication vial, drawing needle, injection needle, syringe, alcohol swab, sharps container.
3. Clean the vial top with an alcohol swab. Let it air dry for 10 seconds.
4. Draw your dose: Attach the drawing needle (18–21g) to the syringe. Draw air equal to your dose volume, inject air into the vial, then invert and draw your prescribed amount. Tap out air bubbles.
5. Switch needles: Remove the drawing needle, attach the injection needle (27–30g, ½ inch).
6. Choose your site: Belly fat (2 inches from navel) or love handle area. Alternate sides each injection.
7. Clean the injection site with a fresh alcohol swab. Let it dry.
8. Pinch an inch of skin and fat between your thumb and forefinger.
9. Insert the needle at a 45-degree angle in one smooth motion. Don't hesitate — a quick, confident motion hurts less.
10. Inject slowly — take 10–15 seconds to push the plunger. Rushing causes more post-injection discomfort.
11. Withdraw the needle straight out. Don't rub the site — just apply light pressure with a cotton ball if needed.
12. Dispose of the needle immediately into your sharps container. Never recap.

Intramuscular Injection — Step by Step

1. Steps 1–4 are identical to SubQ (wash hands, prep supplies, clean vial, draw dose).
2. Switch to IM needle: Attach a 22–25g, 1–1.5 inch needle.
3. Choose your site: Upper outer quadrant of the glute (ventrogluteal is safest), outer mid-thigh (vastus lateralis), or deltoid.
4. Clean the site with an alcohol swab.
5. Spread the skin taut with your non-dominant hand (Z-track technique: pull skin to the side before inserting).
6. Insert at 90 degrees in one smooth, dart-like motion.
7. Aspirate (optional): Pull back slightly on the plunger. If blood appears, withdraw and try a new site. Most current guidelines consider aspiration unnecessary for the recommended sites.
8. Inject slowly over 15–20 seconds.
9. Withdraw and release the skin. Apply gentle pressure. A small amount of bleeding is normal.
10. Dispose safely in sharps container.

Injection Site Rotation Schedule

Rotating sites prevents scar tissue buildup and ensures consistent absorption. Here's a simple rotation:

Injection Day	SubQ Sites	IM Sites
Injection 1	Left abdomen	Right ventrogluteal
Injection 2	Right abdomen	Left ventrogluteal
Injection 3	Left love handle	Right vastus lateralis
Injection 4	Right love handle	Left vastus lateralis
Injection 5	Left upper thigh	Right deltoid
Injection 6	Right upper thigh	Left deltoid

Then repeat. Keep a simple log — even a note on your phone — tracking which site you used last.

Common Mistakes to Avoid

• Using the same needle to draw and inject. Drawing through the rubber stopper dulls the needle significantly. Always swap.
• Injecting too fast. Rushing causes post-injection pain and knots. Take your time.
• Not rotating sites. Same spot every time leads to scar tissue that makes future injections harder and affects absorption.
• Injecting cold oil. Let your vial sit at room temperature for 10 minutes before injecting. Warm oil flows easier through the needle.
• Rubbing the injection site. This can push the oil back toward the surface. Light pressure only.
• Skipping hand-washing. Infection risk is low but real. Don't cut corners.
• Hesitating during insertion. A quick, confident motion hurts far less than slowly pushing through the skin.

Frequently Asked Questions

This guide is for educational purposes. Always follow the specific instructions provided by your prescribing clinician. HeydayMD connects men with licensed clinicians for personalized hormone health evaluation. Not all individuals qualify for treatment. Results vary.