Which three sites does the label allow?
Semaglutide goes into the fatty layer just under the skin, and the Wegovy label lists three places to put it: the abdomen, the thigh and the upper arm. It is not a muscle shot, so the needle is short and only needs to reach the fat.
| Site | Where exactly | Practical notes |
|---|---|---|
| Abdomen | Lower belly, at least 2 inches from the belly button | Easiest to see and reach; plenty of room to rotate |
| Thigh | Front of the upper leg | Easy to reach sitting down; good when the belly is sore |
| Upper arm | Back of the upper arm | Hard to reach alone; some product instructions suggest having someone else give it there |
The label also reports that semaglutide reaches similar levels in the blood from all three sites, and it says the injection site and time of day can be changed without changing your dose. Pick the site you can reach steadily and see clearly.
How do you rotate injection sites?
Use a different spot with every dose. The Wegovy label says to rotate injection sites each time, and MedlinePlus advises keeping each new subcutaneous injection at least 1 inch from the last one.
A simple rotation for a weekly shot:
- Week 1: left lower belly
- Week 2: right lower belly
- Week 3: left front thigh
- Week 4: right front thigh
- Then start again, shifting an inch or two from where you went last time.
Skip any patch of skin that is bruised, swollen, tender, firm, lumpy or numb, and stay about 1 inch from scars. MedlinePlus, in its guide to giving an insulin injection, notes that numb or lumpy spots are a common reason an injected medicine does not work as expected, and suggests keeping a simple chart of where you have injected. A note on your phone with the date and site works just as well.
How do you place the needle?
For a pen, follow its instructions for use; the device sets the angle and depth. For a syringe, MedlinePlus describes the standard technique: pinch about an inch of skin and fat, not muscle, and insert the needle at 90 degrees, or at 45 degrees if there is little fatty tissue. Let the skin air dry after an alcohol wipe before you inject.
Our step-by-step guide to injecting semaglutide or tirzepatide walks through the full sequence, including disposal.
How is a pen different from a vial and syringe?
The biggest difference is who measures the dose. Wegovy comes in pens that deliver a fixed dose: the label describes a single-dose pen with a hidden needle that you press firmly against the skin until its yellow bar stops moving, and a single-patient-use pen that holds four doses.
| Brand-name pen | Vial and syringe | |
|---|---|---|
| Who measures the dose | The pen delivers a set dose | You draw it up yourself |
| Needle | Hidden or attached, used once | A fresh syringe and needle each time |
| Main risk | Lifting the pen off too early | Drawing up the wrong amount |
| Typical source | Brand-name Wegovy | Compounded semaglutide |
Vials carry a specific risk. The FDA has reported dosing errors with compounded semaglutide from multiple-dose vials, often from confusion between units, milliliters and milligrams. In the reports it described, some patients injected 5 to 20 times the intended dose, and some needed medical care for nausea, vomiting, dehydration, pancreatitis or gallstones.
If you use a vial, confirm the concentration, the number of units to draw and the syringe size with the clinician and the pharmacy before your first dose. Never reuse needles or share a pen or syringe with anyone. Our comparison of compounded semaglutide and Wegovy explains where compounded versions stand in 2026.
What is normal at the site afterward?
A little soreness, redness or a small bump that fades over a day or two is common. Spreading redness, warmth, swelling that keeps growing, pus or a fever are signs of infection and need a same-day call to your provider.
Facial or throat swelling or difficulty breathing after a shot is an emergency: call 911. For the wider list of side effects to watch for, see our page on semaglutide side effects.
How Ultimate Male helps with your first injections
If you have never given yourself a shot, say so at your consultation for our medical weight loss program. Your provider can go over the sites, the rotation and the device you will use, and answer questions before you are on your own at home.
Our guide to your first medical weight loss visit explains what that appointment covers. If you miss a week along the way, our answer on what to do after a missed semaglutide dose has the label’s timing rules.
