Quick Answer
Weekly GLP-1 pens such as Ozempic, Wegovy, Mounjaro and Zepbound go under the skin (subcutaneous, meaning into the fat layer, not the muscle) of three areas: the abdomen, the front of the thighs or the back of the upper arms. You can stay in the same area, but the manufacturers' instructions say to change the exact spot every injection. A four-week rotation through four zones of the belly, or alternating belly and thighs, keeps every spot rested.
This is general information from the medicines' instructions for use. Your prescriber and pharmacist have the final word for your pen.
Where Can You Inject a GLP-1 Pen?
All the common weekly GLP-1 pens use the same three areas:
| Area | Where exactly | Notes |
|---|---|---|
| Abdomen | Belly fat, at least 5 cm (2 inches) from the navel | Easiest to see and reach yourself |
| Thigh | Front and outer middle of the thigh | Good alternative if the belly is sore |
| Upper arm | Back of the upper arm | Usually needs a second person |
Daily oral Rybelsus is a tablet, so there is nothing to rotate.
Why Rotate Injection Sites?
Using the same spot again and again can leave the skin sore, bruised or with lumps under it. Lumpy, thickened fat (lipohypertrophy) is well known from insulin users and can change how a medicine is absorbed.
Rotating spreads the small trauma of each shot across a larger area. It is also the instruction printed in the patient leaflets for semaglutide and tirzepatide pens.
A Simple Four-Week Rotation Plan
- Split your belly into four zones around the navel: upper left, upper right, lower left, lower right.
- Week 1: inject in the upper left zone.
- Week 2: upper right.
- Week 3: lower left.
- Week 4: lower right, then start again.
- Within a zone, move a finger's width away from last time's spot.
If you prefer, replace two belly zones with your left and right thighs. The rule is the same: no spot twice in a row.
Where Not to Inject
- Skin that is tender, bruised, red, scaly or hard
- Scars, stretch marks, moles or tattoos
- Within 5 cm of the belly button
- Right next to an insulin shot, if you also inject insulin (use a different spot in the same area)
If a site stays red, swollen or painful for more than a few days, show it to your doctor or pharmacist.
How to Remember Which Spot You Used
A rotation is only as good as your memory of last week. Three options:
- Paper: a small drawing of your body on the fridge, with the date next to each spot
- Phone notes: one line per shot with date, dose and site
- A GLP-1 tracker: an app that stores each site and suggests the next one
We built Pali at bmnova for exactly this. Each shot is logged on a body map that remembers the spots used in the last two weeks and suggests a rested one. You can add a pain score, so you see which areas hurt less for you, and the doctor report shows the history at your next appointment.
FAQ
Can I inject Ozempic or Mounjaro in the same area every week? Yes, you can stay in the same area, such as your belly. The instructions say to use a different spot within that area each time.
Does the injection site change how well a GLP-1 works? The labels for semaglutide and tirzepatide allow the abdomen, thigh and upper arm without changing the dose. Lumpy or scarred skin can affect absorption, which is why rotating matters.
Which GLP-1 injection site hurts the least? It varies by person. Many people find the belly easiest, while others prefer the thigh; logging a pain score after each shot shows you your own pattern.
What should I do if I get a lump or bruise at the injection site? Small bruises and redness usually fade in a few days; skip that spot until it does. A lump that stays, spreads or hurts should be checked by your doctor or pharmacist.
How far apart should GLP-1 injection spots be? Move at least a finger's width (about 2–3 cm) from your last spot, and keep 5 cm away from the navel.