How to Inject Semaglutide: A Step-by-Step Guide

Semaglutide, the active ingredient in Ozempic® and Wegovy®, is a glucagon-like peptide-1 (GLP-1) receptor agonist taken as a once-weekly injection. It’s administered with a tiny needle that punctures the top layer of your skin. Once you know how to inject semaglutide, it’s actually pretty easy—and nearly pain-free. 

Injecting semaglutide might seem intimidating, especially if it’s your first time. And it’s totally normal to be nervous. But with solid instructions, you’ll feel more prepared and confident.

We’ll give you a step-by-step look at what the process entails. Read on to learn exactly how to inject semaglutide safely and comfortably at home.

So, where do you actually inject it? Semaglutide injection sites include three body areas: the abdomen, the front of the thigh, or the upper arm.

You can choose any of these, but you may want to rotate your injection site each week to avoid bruising and minimize the risk of infection.

Now that you know where to inject semaglutide, let’s walk through the steps with Craig Primack, MD, FACP, FAAP, MFOMA. Dr. Primack is a physician specializing in obesity medicine and the Senior Vice President of Weight Loss at Hims & Hers.

Here’s exactly how to inject semaglutide.

Gather Supplies and Your Wash Hands

This is the time to ensure all your ducks are in a row. You’ll need:

• The vial of your prescription medication

• A sterile syringe and needle (use a new needle each time)

• An alcohol swab or wipe

Wash your hands with soap and water, and make sure the area around you is clean.

Know Your Dose

Your provider will instruct you on your semaglutide dosing schedule. Most people start on a low introductory dose (0.25 milligrams) and slowly increase their dose over time as their bodies adjust to the medicine. 

When you go to measure your dose, you’ll notice that the syringes you received with your treatment kit are marked in “units” — not milligrams (mg). 

This may seem confusing at first. But don't worry — instructions from your provider will detail how many units you should measure out for each dose. 

Prepare the Injection

This will probably be the most time-consuming step, but it gets easier with practice and should take just a few minutes.

1. Take the sterile cap off the GLP-1 medication and wipe the top of the medication vial with an alcohol swab. 

2. Remove the protective cap from the end of the syringe and the cap from the tip of the needle.  

3. Pull back on the plunger to draw air into the syringe. You should pull it down to the same volume as your prescribed dose.

4. Puncture the top of the medication vial with the needle and push the air into the vial. This breaks the vacuum seal, making it easier to withdraw the medication.

5. Hold the vial and syringe upside down in one hand. Use your other hand to slowly pull the plunger back and withdraw the semaglutide to the correct dose.

6. Carefully remove the needle from the vial, being mindful not to bend the needle.

7. Lightly tap or flick the syringe to see if any air bubbles rise to the top. If they do, gently push the plunger to remove them. If you’ve removed fair bubbles, you may need to add a little more medication to get the correct dose.

Insert the Medication

Your injection is now ready to go. Just make sure not to touch the needle (or let it come into contact with anything else).

This should go without saying, but you’ll need to inject directly into bare skin (i.e., not through clothing).

Now, here’s how to inject your semaglutide medication:

1. If you want, you can pinch a section of skin at your injection site of choice. This might make it easier to insert the needle.

2. Hold the syringe between your index and middle finger, with your thumb on the plunger.

3. Position it at a 90-degree angle to your body, then carefully and slowly insert the needle all the way into your skin.

4. Gently push the plunger down until it meets the bottom when all the medication has been injected.

5. Once all the medication has been injected, gently remove the needle from your skin.

Discard the Syringe and Clean Up

As soon as you’re finished, throw away the used needle somewhere hard and enclosed (like a sharps container, an empty laundry detergent canister, or food containers).

Also, don’t attempt to put the cap back on the syringe because you might accidentally poke yourself.

Then, place your medication vial back in the fridge for future use.

Side note: Once empty, you can throw away the vial in a normal trash bin.

Still have lingering questions? Find answers to frequently asked questions about how to inject semaglutide below.

What’s the Best Place to Inject Semaglutide?

There is no specific spot that is most effective for semaglutide injections, so there is no “best” injection site. As long as you stick within the recommended areas of the abdomen, thigh, or upper arm, you’re good to go.

What Time of Day Should I Inject Semaglutide?

You can do your weekly semaglutide injection any time of day. However, it is recommended  to do it around the same time each week, whether in the morning or right before bed. This consistency may help with the absorption rate and steady blood sugar levels.

How Often Should You Rotate Semaglutide Injection Sites?

Some people opt to rotate their semaglutide injection site each week. For example, you can alternate between the left and right sides of your chosen body area. This can help prevent discomfort or changes to the skin at the injection site (like scar tissue buildup).

Why Do You Inject Semaglutide?

You may be wondering why semaglutide medications are subcutaneously injected once a week. As research shows, injecting certain medications right under your skin allows them to be more slowly absorbed over a sustained period. In other words, it enters your bloodstream gradually, over the course of several days, rather than all at once.

What Should You Look Out for After Injecting Semaglutide?

You may notice some redness or discomfort at the injection site. This is normal. But if you see signs of an allergic reaction (like a rash or hives), contact a healthcare professional immediately.

When Does the Semaglutide Vial Expire?

Once punctured, each vial has an expiration date of 28 days. So, even if your vial still has meds in it after 28 days, you’ll need to toss it out.

What Should I Do If I Miss a Dose of Semaglutide?

If you miss a dose, take it within five days of that missed dose. But if it’s been more than five days since your missed dose, skip it and continue with your regular injection schedule, taking your next dose on the day it was planned.

What Are Common Semaglutide Side Effects?

Common semaglutide side effects include: 

• Nausea

• Vomiting

• Diarrhea

• Stomach pain

• Constipation

Other less common potential side effects of semaglutide include:

• Hypoglycemia (low blood sugar)

• Redness or discomfort at the injection site

• Increased amylase and lipase (enzymes that break down carbs and fats)

• Gallstones

• Increased heart rate

• Fatigue

• Changes in taste in foods

• Dizziness

Serious (and rare) semaglutide side effects:

• Pancreatitis (inflammation of the pancreas) 

• Diabetic retinopathy complications

• Hypoglycemia (low blood sugar) when used with an insulin secretagogue or insulin 

• Acute kidney injury 

• Hypersensitivity reactions

There’s also a black box warning that semaglutide can cause thyroid C-cell tumors in rodents. That said, it’s unclear if the medication can cause these tumors or thyroid cancer in humans.

Still, semaglutide isn’t safe for people with a personal or family history of medullary thyroid carcinoma or those with multiple endocrine neoplasia syndrome type 2.

There isn’t enough research on whether semaglutide is safe for people who are pregnant or breastfeeding. If you’re pregnant, breastfeeding, or planning to be soon, let your healthcare provider know. 

How Long Before Semaglutide Starts Working?

Since everyone is different, it can vary.

But Novo Nordisk (the manufacturer of Ozempic and Wegovy) claims that semagtlude’s concentration in the bloodstream typically reaches a steady level after four or five weeks of use. So you may notice changes in appetite a little before then.

One clinical trial looked at almost 2,000 adults without diabetes who took a weekly semaglutide injection, ate healthier, and incorporated more movement into their days.

It found that:

• On average, people lost over four percent of their body weight after eight weeks on semaglutide.

• Those who took the highest dose available (2.4 milligrams a week) lost an average of 10.6 percent of their total body weight after 20 weeks.

• After 68 weeks, they lost almost 15 percent of their body weight.

Other GLP-1 medications with different active ingredients — like Mounjaro® (tirzepatide) — will have a slightly different timeline.

Injecting semaglutide may seem a little nerve-wracking at first. But hopefully, now that you have a simple step-by-step guide, you’ll feel more confident and empowered to administer it yourself.

Here’s what to keep in mind about injecting semaglutide:

• Semaglutide injections can treat type 2 diabetes and overweight or obesity (and associated risks, like heart disease) when coupled with a healthy diet and regular exercise.

• Injecting semaglutide will unfold in four steps: sanitizing, prepping, injecting, and cleaning up.

• Your injection site should be rotated every week, and you can choose between your stomach, upper arm, or thigh.

• When in doubt, follow the semaglutide injection directions from your prescribing healthcare provider.

If you’re interested in compounded semaglutide, you can start a consultation with a weight loss specialist at Hers. They’ll help you develop a treatment plan tailored to your specific needs.