Page last checked 2026-09-07

How-to · injection guide

How to inject Semaglutide

Semaglutide injections go under the skin, not into muscle, once a week. You use the abdomen, thigh or upper arm, moving to a different spot each time, and you pick a day of the week and keep to it.

A prescriber or pharmacist should show you how to use the exact pen, syringe or vial you receive. Changing devices may change the steps.

What matters first

Where it goes: Under the skin of the abdomen, thigh or upper arm
How often: Once each week, on the same day
If the day changes: Ozempic: more than 48 hours. Wegovy: 2 or more days.

Ozempic and Wegovy have injectable forms. Semaglutide also comes as tablets, including Rybelsus and Wegovy tablets; those are taken by mouth.

Medically reviewed by Kenneth Montecillo, MD2026-09-07open the primary sources

Where does semaglutide go?

Under the skin of the lower stomach, the front of the thigh and the back of the upper arm. Stay 2 inches (5 cm) from the belly button.

A front and a back body outline. They mark where Semaglutide goes under the skin: the lower stomach, the front of the thigh and the back of the upper arm. The area around the navel is hatched out. The label says to stay 2 inches (5 cm) from the belly button. Open circles inside each area are the spots to move between. One filled circle is this dose. The label says to use a different spot for every dose. The same body area can be used each week, as long as it is not the same spot. Never into muscle or a vein. And not skin that is tender, bruised, red or hard, or areas with scars or stretch marks. — Front and back, with the label’s own sites marked. The circles inside each area are the point of the drawing: they are spots to move between, not spots to hit.

Rotation: A different spot for every dose — the same body area can be used each week, as long as it is not the same spot.
Never into: Muscle or a vein. Not skin that is tender, bruised, red or hard, or areas with scars or stretch marks.

FDA labelSource: Wegovy (semaglutide) — FDA-approved Prescribing Information (DailyMed) · retrieved 2026-08-20

What does the label actually say?

Route. Subcutaneous only — the fat layer just under the skin, never a muscle or a vein.
Timing. Once a week, same day, food or no food. Ozempic’s prescribing information gives a 2-day interval and specifies more than 48 hours between doses. Wegovy’s Medication Guide says the last injection must have been given 2 or more days before. Check the instructions for your brand when changing the weekly day.
Sharing. Pens and needles are never shared, even with a fresh needle.

FDA labelSource: Wegovy (semaglutide) — FDA-approved Prescribing Information (DailyMed) · retrieved 2026-08-20

How many units is each label dose?

A branded pen measures the dose for you. A vial does not — you draw it by volume, and every step of the schedule becomes a different number of units on the syringe. The table holds the water volume fixed so the steps line up side by side.

◆ Label doses at 5 mg in 2 mLU-100 syringe

Step	Label dose	Volume	Draw to
1	0.25 mg	0.10 mL	10.0 units
2	0.5 mg	0.20 mL	20.0 units
3	1 mg	0.40 mL	40.0 units
4	1.7 mg	0.68 mL	68.0 units
5	2.4 mg	0.96 mL	96.0 units

Straight arithmetic for a 5 mg vial in 2 mL, where 1 U-100 unit = 0.01 mL. The doses come from the label; the unit column is the math at this example concentration. Branded pens and vials may have a different strength; these units do not replace their instructions.

Compute this for your own vial and water →

Check the product before using an injection guide

Semaglutide comes as injections and tablets. This guide covers injections only. The brand and device determine which instructions apply, including what to do after a missed dose. The schedule shown below does not replace the instructions for the product you receive.

Does all of it have to be injected?

No. Ozempic is an injection. Wegovy has both injection and tablet forms, and Rybelsus is a tablet. An injection guide does not cover how to take a tablet, even when both contain semaglutide. Check the full product name and form on the package before using the steps below.

The drug name alone cannot tell you which device or form you have. A pen, a vial and a tablet require different steps. If the package does not match the device described here, ask the pharmacist to show you the instructions that belong to it.

Why is the interval a week?

The page puts the time it takes the body to clear half of it at one week. A weekly injection therefore arrives while about half of the last one is still there. The level in the blood stacks up over the first month or so. It does not peak and vanish between doses.

Half-life does not set the rules for a missed dose or a change of day. Those rules come from the product label. Use the brand-specific timing section on this page rather than working out a new interval from how long the drug stays in the body.

Where does this schedule end?

Not at one place. Its last two steps are both marked as places to stay. The end of this schedule is a decision rather than a summit. The prescriber makes it, on how the drug has been tolerated.

The two final doses require different syringe draws from the same vial. The unit table shows both, which is why the full schedule matters.

What should you do after a missed dose?

Both injectable brands have missed-dose instructions, but they use different timing rules. Ozempic counts time since the missed dose. Wegovy also considers how close the next scheduled injection is. The brand-specific missed-dose section on this page gives the labeled intervals.

A gap of several weeks raises a separate question about restarting Wegovy. Its Medication Guide says to contact the prescriber after multiple missed weeks. Tablet instructions are different again. Check the package directions or ask your pharmacist if you are unsure which rule applies to your product.

Does the label say how far from the navel?

This label gives the clearance in both inches and centimeters. Labels for drugs in the same class can use different instructions, so each one is kept as written.

Where a label is silent, the page is silent too. A distance that looks precise but came from us rather than the label would be the least trustworthy number on the screen.

Why does the site have to move?

Using the same spot over and over hardens the tissue underneath, and hardened tissue absorbs differently. Since absorption decides how much of a dose actually reaches you, moving the site is about consistency as much as comfort. The label directs rotation between doses, and against injecting skin that is already tender, bruised, red or hardened.

Private rotation log

Keep track of where you injected

stays on this device

Save the date, body area and a short note about the spot. This log records your choice; it does not choose an injection site for you.

Injection date

Body area

Note about the exact spot (optional)

Where does the needle go afterwards?

Used needles belong in an FDA-cleared sharps container, or failing that a heavy-duty plastic container with a tight lid — never loose in household trash or recycling. What happens to a full container is set locally rather than federally, so collection varies by state and city.

Boxed warning

Risk of thyroid C-cell tumors

Semaglutide caused thyroid C-cell tumors in rodents. It is not known if this happens in people. The label rules it out for anyone with a personal or family history of MTC or MEN 2.

Questions people ask about injecting semaglutide

Where is semaglutide injected?

Under the skin of the abdomen, thigh or upper arm, moving spot between doses. The label does not describe injecting into muscle or a vein.

Does the injection site change how well it works?

The label permits these sites without calling one best. Use a different spot for each injection and follow the device’s instructions about skin to avoid.

Can the injection day be changed?

Ozempic’s prescribing information gives a 2-day interval and specifies more than 48 hours between doses. Wegovy’s Medication Guide says the last injection must have been given 2 or more days before. Check the instructions for your brand when changing the weekly day.

What happens if a dose is missed?

Ozempic allows a missed dose within 5 days; after that, skip it and return to the usual day. Wegovy instead uses the time until the next dose: take the missed injection if the next one is more than 48 hours away, or skip it if less than 48 hours away. Ask your pharmacist if the timing is unclear. After 2 or more missed weeks of Wegovy, contact your prescriber about restarting. These are injection rules; tablets have different instructions.

Does the injection hurt?

Pain, redness or irritation can occur at the injection site. The label does not predict what one person will feel. Ask your care team about persistent or worsening reactions.

Is the technique the same for a vial as for a pen?

The route and the sites are the same, but a pen measures the dose for you and a vial makes you draw it. That is where the unit table above comes in — and where reaching for a U-40 syringe instead of a U-100 would put you 2.5 times out.

Dosage chart and titration schedule

The label schedule week by week, with the source on every row.

Semaglutide side effects

Common and serious reactions, each quoted from the label.

These steps summarize the prescribing label. They do not replace the injection training the clinician or pharmacist who dispenses the product gives you, and nothing here recommends a dose.

Questions readers ask

How long does it take to lose 20 lb on semaglutide?

No trial here publishes a time to any weight in pounds, so there is no honest schedule to give. What SURMOUNT-5 measured was percentages over a fixed stretch of time.

Over 72 weeks, 751 adults with obesity lost a mean 13.7% of body weight on semaglutide and 20.2% on tirzepatide. On a 150 lb start, 13.7% comes to about 21 lb — that is arithmetic on an average, not a finding. A mean describes a group, and nobody in it is the average.

Can I inject semaglutide wrong?

Yes, and the label names the ways it knows about. It states a clearance of 2 inches (5 cm) from the belly button, and a different spot for every dose.

It also names skin to leave alone: tender, bruised, red or hard skin, and areas with scars or stretch marks. The same body area can be used each week, as long as it is not the same spot.

Where is the best place to inject semaglutide?

The label names three and ranks none: the lower stomach, the front of the thigh, and the back of the upper arm.

What it does insist on is movement. The same body area can come round again each week, but the same spot cannot. Around the stomach it asks for 2 inches (5 cm) of clearance from the belly button.

What time of day should I inject my semaglutide?

The label sets a weekly interval, not an hour, and it names no time of day at all. The day of the week is the unit that matters.

This page gives semaglutide a half-life of about seven days. One dose is still in the body when the next falls due. An hour either way is a small shift against that.

Where to read next about semaglutide

This page stops at the injection. These carry what happens either side of it.

How semaglutide differs from the rest of its class

The FDA label gives a 5-step dosing schedule for semaglutide.

Refrigerating the Wegovy carton of semaglutide

1 place where this label says nothing, kept visible rather than filled from another semaglutide carton.

The syringe scale for a semaglutide vial

The syringe scale is the fourth thing the semaglutide calculator asks you for.

Storing Ozempic, the semaglutide carton

Ozempic carries semaglutide and allows 28 or 56 days out of the fridge — a semaglutide figure that belongs to this carton alone.

The Zepbound vial draw for a semaglutide vial

The Zepbound vial draw is the fourth thing the semaglutide calculator asks you for.

2primary sources, each with the day we read it — open the documents used on this page

Ozempic prescribing information and Medication Guideretrieved 2026-09-13FDA label
Wegovy prescribing information and Medication Guideretrieved 2026-09-13FDA label