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How to Inject GLP-1 in the Stomach: What Pen IFUs Say

By Dosinha Team | Updated | 7 min read

In this guide
  1. Start with the right instructions
  2. Where the stomach fits
  3. What the single-dose pen IFUs describe
  4. Pens where you attach a needle
  5. What the IFUs say about blood, drops and leaks
  6. When to call someone
  7. Frequently asked questions
  8. Keep a record of where each shot went
  9. Sources

This article is for information only and is not medical advice. Talk to your prescriber or a qualified professional.

If you inject a GLP-1 pen in your stomach, the manufacturers’ Instructions for Use (IFUs) say to choose a spot on the abdomen away from the belly button, clean the skin if your IFU says to, and then follow the pen’s own steps until it signals the dose is done. The exact steps differ from pen to pen. The IFU that came with your pen is the authority, and your prescriber or pharmacist should train you before your first shot. This page restates what the current IFUs say. It covers prefilled pens only.

About Dosinha: a shot log, reminders, injection-site rotation, weight and water are free forever. See what is free and what Pro adds.

Start with the right instructions

Brand names matter here because the devices are not the same.

The labels for Zepbound and Mounjaro also list vials, and the Ozempic label also lists a prefilled syringe. Those use different techniques and are not covered here. If you were given one, ask your pharmacist to walk you through its IFU.

The IFU comes in the medicine box, and DailyMed hosts the current versions (linked in Sources). For where to inject and how to keep track, see our guide to injection site rotation and logging.

Where the stomach fits

According to the Wegovy prescribing information, the site options are the abdomen, thigh or upper arm. The Ozempic label says the same. The Zepbound and Mounjaro labels say abdomen or thigh, and the back of the upper arm only when another person gives the injection.

Some IFUs add detail for the stomach:

All of these IFUs say to avoid skin that is tender, bruised, red or hard, and the Wegovy IFU adds scars and stretch marks. They also say to rotate. Per the Wegovy, Zepbound and Mounjaro IFUs, you can stay in the same body area each week as long as it is not the same spot.

What the single-dose pen IFUs describe

These show the general shape of a pen injection. Check your own IFU for the full text.

Wegovy single-dose pen

  1. Wash your hands. Check that the pen is not used or broken, the medicine looks clear and colorless through the window, and the expiration date has not passed.
  2. Choose a site. Clean it with an alcohol swab or soap and water, then let the skin dry.
  3. Pull the pen cap straight off.
  4. Push the pen firmly against your skin and keep pressing until the yellow bar stops moving. The IFU says you will hear two clicks, one when the injection starts and one while it continues.
  5. Put the used pen in a sharps container right away.

The IFU says the dose is already set on the pen and not to lift it from the skin before the yellow bar stops. If the bar does not move, it says to press more firmly.

Zepbound and Mounjaro single-dose pens

  1. Take the pen out of the refrigerator and leave the gray base cap on. Check the label and dose, the expiration date, and that the pen is undamaged. The medicine should not be frozen or cloudy and should have no particles. Wash your hands.
  2. Choose a site and rotate it each week.
  3. Pull off the gray base cap while the pen is locked. Do not put the cap back on.
  4. Place the clear base flat against your skin, then unlock the pen by turning the lock ring.
  5. Press and hold the purple button for up to 10 seconds. The IFU describes a first click when the injection starts and a second click when it is done. It is complete when the gray plunger is visible.
  6. Put the used pen in a sharps container.

These IFUs also say air bubbles are normal, a drop of liquid on the needle tip is normal, and it is not necessary to warm the pen to room temperature.

Pens where you attach a needle

Two other designs work differently, which is exactly why one set of steps cannot cover every pen.

Ozempic pen. The IFU says to use a new needle for every injection, remove both needle caps, and check the flow only the first time you use a new pen. After you select the dose, you insert the needle as your healthcare provider showed you, press and hold the dose button until the counter shows 0, and count 6 seconds before removing the needle. The IFU says not to put the caps back on the needle, and to put the used needle in a sharps container.

Mounjaro KwikPen. The IFU says to attach a new pen needle, prime the pen before each weekly injection, dial the dose until the knob stops, push the knob in, and slowly count to 5 before pulling the needle out. Do not transfer medicine from the pen into a syringe.

What the IFUs say about blood, drops and leaks

A drop of blood or liquid at the site is described as normal in the Zepbound IFU. It says to press a cotton ball or gauze on the spot and not to rub. The Wegovy IFU says to press lightly with gauze if blood appears. If the pen does not do what the IFU describes, for example the Wegovy yellow bar does not move or the Zepbound gray plunger is not visible, the IFUs tell you to contact your healthcare provider or the manufacturer rather than guess.

Injection site reactions are listed in the labels. The Zepbound label groups bruising, redness, itching, pain and rash under that heading. The Wegovy label lists itching, redness and inflammation, among others. That is the official answer on whether injections can hurt: some people have site reactions, and the labels do not promise a painless shot.

When to call someone

Contact your prescriber or pharmacist if a pen will not work, you are unsure you received the full dose, or a site looks or feels wrong.

The Medication Guides for Wegovy, Ozempic and Zepbound say to stop using the medicine and call your healthcare provider right away for severe stomach pain that will not go away, with or without vomiting, which may spread to your back. The Zepbound guide says to get medical help right away for signs of a serious allergic reaction, such as swelling of the face, lips, tongue or throat, trouble breathing or swallowing, or severe rash or itching.

Your prescriber and pharmacist set your plan. For what the labels say about doses and timing, read GLP-1 dosage: what the labels say and missed a GLP-1 dose? what to read first.

Frequently asked questions

Do GLP-1 injections hurt?

The labels list injection site pain, bruising, redness and itching among the reactions people report, so some discomfort can happen. The IFUs do not describe a technique that removes it. Your pharmacist can watch you inject and answer technique questions.

How far from the belly button should I inject?

The Wegovy single-dose pen IFU says to keep 2 inches away from the belly button when using the lower stomach. The Zepbound and Mounjaro KwikPen IFUs say at least 2 inches. Check the IFU for your own pen.

Can I use the same area every week?

The Wegovy, Zepbound and Mounjaro IFUs say you can use the same body area, as long as you do not use the same spot each time. The Ozempic label says to use a different site each week within the same region.

Keep a record of where each shot went

Dosinha’s shot log has a body map, so you can tap where each shot went and see the last few spots at a glance. You can also note anything unusual at the site to bring to your prescriber. The shot log and rotation map are free. Try the free log.

Sources

This article is for information only and is not medical advice. Talk to your prescriber or a qualified professional.