Medically reviewed by a licensed healthcare professional. Last updated March 2026.
Before Your First Injection
If you have never injected a medication before, know that you are not alone. Millions of people self-inject GLP-1 medications every week. The needles are extremely thin (30 to 32 gauge), and most patients describe the sensation as a small pinch that lasts a few seconds, significantly less painful than a typical blood draw.
Your prescriber's office or pharmacist should demonstrate the injection process during your first visit. This guide serves as a reference for at-home use.
What You Will Need
- Your semaglutide pen (Ozempic or Wegovy)
- A new pen needle (if using Ozempic multi-dose pens; Wegovy pens have needles attached)
- An alcohol swab
- A sharps disposal container (FDA-cleared or a heavy-duty plastic container with a screw-on lid)
Step-by-Step Injection Guide
Step 1: Prepare the Pen
Remove the pen from the refrigerator 15 to 30 minutes before injecting. Injecting cold medication can cause more discomfort at the injection site. Check the expiration date on the pen. Inspect the solution through the pen window. It should be clear and colorless. Do not use it if it appears cloudy, discolored, or contains particles.
For Ozempic pens: Attach a new pen needle by removing the paper tab from the needle, pushing it straight onto the pen, and twisting until snug. Remove the outer needle cap (keep it for disposal later) and the inner needle cap (discard).
For Wegovy pens: The needle is already attached. Remove the pen cap.
Step 2: Check the Flow (Ozempic Only)
If this is a new Ozempic pen (first use), you need to check the flow to ensure the pen is working:
- Turn the dose selector to the flow check symbol (small dot or line, depending on your pen model)
- Hold the pen with the needle pointing up
- Press and hold the dose button until the dose counter shows "0"
- A small drop of semaglutide should appear at the needle tip
- If no drop appears, repeat up to 6 times. If still no drop, use a new needle. If that does not work, use a new pen.
Wegovy pens do not require a flow check.
Step 3: Set Your Dose (Ozempic Only)
Turn the dose selector until your prescribed dose number appears in the dose window. You will hear a click for each increment. If you accidentally select the wrong dose, simply turn the selector forward or backward to correct it.
Wegovy pens are pre-set to a single dose and do not have a dose selector.
Step 4: Choose Your Injection Site
Semaglutide is injected subcutaneously (into the fat layer just under the skin). The three approved injection sites are:
- Abdomen: At least 2 inches from your belly button. This is the most common site and typically the easiest for self-injection.
- Front of thigh: The middle third of the outer front thigh.
- Upper arm: The back of the upper arm (this site usually requires someone else to administer).
Step 5: Clean the Site
Wipe the chosen injection area with an alcohol swab in a circular motion. Let it air-dry completely before injecting. Injecting through wet alcohol can sting.
Step 6: Inject
- Pinch a fold of skin at the injection site with your non-dominant hand
- Insert the needle straight into the skin fold at a 90-degree angle with a quick, firm motion
- Press the dose button (Ozempic) or push the pen firmly against the skin until you hear a click (Wegovy)
- Hold the button down or keep the pen pressed against the skin for a slow count of 10 seconds. This ensures the full dose is delivered.
- Release the skin fold
- Pull the needle straight out
A tiny drop of blood or medication at the injection site is normal and nothing to worry about. Do not rub the area.
Step 7: Dispose of the Needle
For Ozempic: Carefully place the outer needle cap back on the needle (do not use the inner cap). Unscrew the needle from the pen and drop it into your sharps container. Replace the pen cap.
For Wegovy: Each pen is single-use. Place the entire pen into your sharps container.
Never throw loose needles in the regular trash or recycling.
Injection Site Rotation
Rotating your injection site is critical for long-term use. Injecting in the same spot repeatedly can cause:
- Lipodystrophy: Hardened lumps or dimpled areas under the skin
- Reduced absorption: Scar tissue absorbs medication less effectively
- Pain and bruising: Overused sites become more sensitive
Rotation strategy: Think of your abdomen as a clock face. Start at 12 o'clock (above the navel) and move one position clockwise each week. After completing the circle, switch to your thigh for a few weeks, then back to the abdomen. Keep at least 1 inch between injection sites.
Some patients keep a simple log or use the day of the month to determine their site. The specific system matters less than being consistent about not reusing the same spot.
8 Common Injection Mistakes
1. Not letting the pen warm up
Cold medication causes more stinging and discomfort. Remove the pen from the fridge 15 to 30 minutes before injecting.
2. Injecting into muscle instead of fat
If you are lean, pinching a skin fold is essential. Injecting into muscle can alter absorption speed and may cause more pain.
3. Not holding long enough after pressing the button
Releasing too early means you do not get the full dose. Count to 10 slowly. With Wegovy pens, wait for the second click.
4. Reusing needles (Ozempic)
Used needles become dull and can introduce bacteria. Always use a new needle for each injection.
5. Injecting through clothing
Always inject on bare skin. Fabric can deflect the needle or introduce lint and bacteria.
6. Forgetting the flow check on a new Ozempic pen
Skipping the flow check on a new pen may result in receiving less than your full dose on the first injection.
7. Not rotating injection sites
Injecting in the same spot every week leads to lipodystrophy and reduced medication absorption.
8. Squeezing the skin fold too tightly
A gentle pinch is sufficient. Squeezing too hard can cause bruising and discomfort.
Proper Needle and Pen Disposal
FDA regulations require that used needles and pens be placed in a sharps disposal container. Options include:
- FDA-cleared sharps containers: Available at pharmacies for about $5 to $15
- Heavy plastic household containers: A laundry detergent bottle or similar thick plastic container with a screw-on lid works if a proper sharps container is not available
- Mail-back programs: Some manufacturers and pharmacies offer mail-back sharps disposal kits
- Community drop-off sites: Many pharmacies, hospitals, and fire stations accept sharps containers. Check with your local waste management for drop-off locations.
Never place loose needles in household trash, recycling bins, or flush them down the toilet.
When to Call Your Provider
Contact your prescriber if you experience:
- Persistent pain, redness, or swelling at the injection site lasting more than 48 hours
- A hard lump at the injection site that does not resolve
- Signs of infection (warmth, increasing redness, pus)
- An allergic reaction (rash, hives, difficulty breathing, swelling of the face or throat)
- You are unsure whether you received the full dose
Ready to start your weight loss journey? Find a GLP-1 clinic near you and connect with a qualified provider today.
Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Individual results vary. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you are experiencing a medical emergency, call 911.