Injectable semaglutide — sold as Wegovy and Ozempic — is a once-weekly shot you give yourself under the skin, not into a vein or muscle. The third brand, Rybelsus, delivers the same molecule as a daily tablet, so it isn’t injected at all. This guide covers where the injection goes, how the technique works step by step, the storage and disposal rules, and how oral semaglutide differs.
Where to inject semaglutide
Semaglutide goes into subcutaneous fat — the soft layer just under the skin — at one of three sites (⚠ verify descriptions against your Instructions for Use):
- Abdomen (belly) — the most common spot. Stay at least 2 inches away from your navel in any direction. Most people find the stomach the easiest area to see and reach.
- Front of the thigh — the fleshy area on the top and slightly outer part of the upper leg, between hip and knee.
- Back of the upper arm — the fatty area behind and below the shoulder. It’s the hardest to reach yourself, so many people save it for when someone can help.
All three absorb the medicine equally well, so the choice comes down to comfort and reach. Whichever area you pick, avoid skin that’s bruised, tender, hard, lumpy, scarred, or red. And rotate — repeatedly injecting the same patch can build up lipohypertrophy, thickened fatty lumps that make future doses absorb unevenly. More on the rotation pattern below.
How to inject semaglutide step by step
This is the general once-weekly technique for the semaglutide pen. The Ozempic pen is a multi-dose dial pen; Wegovy has used single-dose pens — the details differ, so your printed Instructions for Use is the authority. Read it the first time and keep it for reference.
- Wash your hands with soap and water, and gather your pen, a new needle, and a sharps container.
- Inspect the pen and medicine. Check the label and look through the pen window — the liquid should be clear and colorless. Don’t use it if it’s cloudy, discolored, or has particles.
- Let it reach room temperature. Injecting straight from the fridge stings more; many people take the pen out a little ahead of time (⚠ verify any timing against the IFU). Never warm it in a microwave or hot water.
- Attach a new needle and remove both needle caps, keeping the outer cap to unscrew the needle later.
- Do a flow check on a new multi-dose pen. The first time you use a fresh Ozempic pen, dial to the flow-check symbol and press until a drop appears at the tip — this clears air and confirms flow (⚠ verify step against the IFU). You don’t repeat this on later injections from the same pen, and single-dose Wegovy pens don’t use this step.
- Set your prescribed dose. On a dial pen the counter shows milligrams; set the exact dose your prescriber gave you — no more, no less. Single-dose pens are pre-set.
- Pick and clean a spot, then position the needle against the skin at the angle your IFU shows (typically straight in, 90 degrees; pinch a fold of skin first if advised).
- Press and hold the dose button until the counter returns to 0, then keep the needle in and count slowly to 6 before pulling it straight out (⚠ verify count against the IFU). This makes sure the full dose goes in.
- Remove and dispose of the needle in your sharps container. Never store the pen with a needle attached; recap the pen and put it away.
If you take Rybelsus (the pill) instead
Oral semaglutide has no injection technique, but it has its own strict rule. Take one tablet first thing in the morning on an empty stomach, swallowed whole with no more than a sip of water (⚠ verify the amount against the label). Then wait 30 minutes before eating, drinking anything else, or taking other medicines — the drug is absorbed poorly, and skipping the wait wastes most of the dose. See the semaglutide dosage guide for how the pill and the shot compare.
Rotating injection sites
Rotating does one job: it protects your skin. Inject the same square inch week after week and the tissue can thicken into lipohypertrophy — firm, rubbery lumps that both look different and absorb medicine less predictably, which can make your dose work less reliably.
A simple rotation that’s easy to remember:
- Rotate between areas across weeks — for example, abdomen one week, thigh the next, upper arm the week after, then back to the abdomen.
- Rotate within an area too. If you use the abdomen two weeks in a row, shift the exact spot by at least an inch, and switch sides of the navel.
- Keep a simple log — a note on your phone or a mark on a calendar — so you’re not guessing where last week’s injection went.
The abdomen has the most usable real estate, which is why many people anchor there and just keep moving the spot around it. Whatever pattern you choose, the principle is the same: never two injections in the same place back to back.
Storing semaglutide
Storage matters because heat and freezing both ruin semaglutide. In-use windows differ by brand, so this is general guidance (⚠ verify every temperature and day figure against the label — novo-pi.com/wegovy.pdf and novo-pi.com/ozempic.pdf):
- Before first use: keep pens in the refrigerator at 36–46°F (⚠ verify). Don’t store them near the freezer coils.
- After first use: an in-use pen can be kept at room temperature below 86°F, or in the fridge, for a set number of days that depends on the brand — for example, up to 56 days for Ozempic (⚠ verify each brand’s window). After that, discard the pen even if medicine remains.
- Never freeze it. A pen that has been frozen is ruined and must be thrown away, even if it looks fine (⚠ verify).
- Rybelsus tablets are stored differently — at room temperature in their original blister and bottle, kept dry (⚠ verify against the label). They aren’t refrigerated.
- Traveling: keep pens cool and out of direct sun — a cool bag without a frozen pack touching the pen. Don’t leave it in a hot car or in checked luggage.
- Always store a pen with the cap on and no needle attached, away from heat and light.
Needles and sharps disposal
Every injection uses a new, single-use pen needle — one needle per dose, never reused and never shared. A fresh needle is sharper, hurts less, and avoids the infection and blockage risks a dull, reused one carries.
Used needles are biohazard sharps and can’t go in household trash or recycling. Handle them this way:
- Drop each used needle straight into an FDA-cleared sharps disposal container — a rigid, puncture-resistant, lidded container made for the purpose.
- If you don’t have one on hand, a heavy-duty plastic container with a tight screw-on lid can work as a temporary stand-in, but a proper sharps container is the right tool.
- Don’t overfill it, don’t recap needles by hand, and when it’s about three-quarters full, seal and dispose of it following your local guidelines — programs vary by state and city.
The FDA’s sharps guidance (linked in Sources) explains local disposal options, from drop-off sites to mail-back programs.
Common mistakes and when to call your clinician
A few errors come up again and again:
- Injecting into muscle instead of fat. Semaglutide is subcutaneous. Going in too deep — wrong angle, or a very lean spot with a long needle — can sting more and change absorption. If you’re lean, pinching a fold of skin helps keep the needle in the fat layer.
- Reusing or not changing needles. One new needle per dose, every time.
- Not rotating sites, which invites the lumps described above.
- Removing the needle too early, before the count finishes, which can leave part of the dose on your skin.
- Taking Rybelsus with food or a full glass of water, which blunts absorption. The empty-stomach, small-sip rule isn’t optional.
- A missed dose. There’s a specific rule for how long a window you have to take it late versus skip it — and it differs by brand. Don’t guess, and never double up. Our missed-dose helper walks you through it.
Mild, short-lived redness, itching, or a small bump at the injection site is common and usually fades on its own. What deserves a call to your clinician: a site reaction that spreads, worsens, or doesn’t settle; signs of infection like increasing pain, warmth, or pus; or any symptom that feels bigger than the injection itself — a rash all over, swelling of the face or throat, trouble breathing, or severe belly pain that won’t go away. Those are not “inject through it” symptoms. When in doubt, see GLP-1 safety and contact your prescriber.
How to inject a GLP-1: the deep guide A fuller walkthrough of technique, site rotation, and troubleshooting across every GLP-1 pen Semaglutide: the complete guide What it is, how well it works, what it costs, dosing, and how to get it