Step-by-Step Guide
GLP-1 Injection Guide
Proper injection technique reduces discomfort, prevents injection-site reactions, and ensures you get your full dose. This guide covers everything from first-time setup to rotation schedules.
Always follow your prescriber's specific instructions. This guide is for general educational purposes. Dosing schedules, pen types, and needle sizes vary by medication and formulation.
Where to Inject
Rotate between sites each week to prevent lipohypertrophy (fatty lumps) that reduce absorption.
Abdomen
Best absorption. Inject at least 2 inches from belly button. Avoid the waistband area.
Outer Thigh
Good alternative. Use outer upper thigh. Avoid inner thigh and knee area.
Upper Arm
Acceptable but hardest to self-inject. Better if someone else can inject for you.
Rotation Strategy
Divide your abdomen into quadrants (upper-left, upper-right, lower-left, lower-right) and rotate weekly. Do the same for thighs. Never inject into the exact same spot twice in a row — this is the most common cause of injection-site reactions and inconsistent drug absorption.
Step-by-Step Injection
Gather your supplies
Pen injector (semaglutide or tirzepatide), alcohol wipe, a cotton ball or gauze. Wash your hands thoroughly.
Remove from refrigerator 30 minutes early
Injecting cold medication increases discomfort and may affect absorption. Let the pen sit at room temperature for at least 30 minutes before injecting.
Prepare the pen
Remove the cap. If it's a new pen, prime it first per your medication's instructions (usually turning the dial to the priming symbol and pressing until a drop appears).
Dial to your prescribed dose
Turn the dose selector to your prescribed dose. Double-check before injecting — don't inject if the dose window looks wrong.
Clean the injection site
Wipe with an alcohol swab and let it dry completely (15–20 seconds). Injecting into wet skin increases sting.
Pinch the skin (if needed)
For lean injection sites or a thin needle gauge, lightly pinch the skin. Most modern pen needles (4–5 mm) don't require pinching.
Insert the needle at 90°
Press the needle straight into the skin at a 90-degree angle in one smooth motion. Do not hesitate — slow insertion hurts more.
Press and hold for 10 seconds
Depress the injection button fully and hold for 10 seconds before removing. This ensures the full dose is delivered.
Remove and dispose
Pull the needle straight out. Apply gentle pressure with a cotton ball — do not rub (rubbing can cause bruising and spread medication). Dispose of the needle in a sharps container.
Storage Requirements
Improper storage degrades the medication and reduces effectiveness.
Unopened pens
Refrigerator (36–46°F / 2–8°C). Do not freeze. Protect from light.
In-use pens (Ozempic/Wegovy)
Refrigerator or room temperature up to 77°F (25°C) for up to 56 days.
In-use pens (Mounjaro/Zepbound)
Refrigerator or room temperature up to 86°F (30°C) for up to 21 days.
Expired or damaged pens
Do not use. Return to pharmacy or dispose per local regulations.
Missed Dose Protocol
Missed by < 5 days (weekly injection)
Inject as soon as you remember. Resume your normal weekly schedule from that new date.
Missed by > 5 days (weekly injection)
Skip the missed dose entirely. Resume on your next regularly scheduled date.
Never double dose
Do not inject extra to make up for a missed dose. This significantly increases side effect risk.
Set reminders
Use a phone alarm or calendar reminder on the same day each week. Consistency improves outcomes and reduces side effect spikes.
Troubleshooting Common Problems
Bleeding at injection site
Normal — small blood vessels are occasionally nicked. Apply gentle pressure for 30 seconds. No need to re-inject.
Burning or stinging
Usually caused by cold medication or injecting into wet skin after cleaning. Let pen reach room temp and let alcohol dry fully.
Lumps or hardness at site
Lipohypertrophy from repeated injections in the same spot. Avoid that area for several weeks and rotate more aggressively.
Pen won't click
Check that the needle is attached correctly. Ensure you're holding the pen firmly against skin. Contact your pharmacy if pen appears defective.
Medication leaked out
If you see a drop on the skin after removing, you likely didn't hold long enough. Count a full 10 seconds next time. Don't re-dose.