The Three FDA-Approved Semaglutide Injection Sites

Semaglutide (Ozempic, Wegovy) is administered subcutaneously—into the fat layer just beneath your skin. Three anatomical regions are approved:

Why the Abdomen Is the Best Injection Site

For most patients, we recommend the abdomen as the primary semaglutide injection site. Here's the science:

Superior Blood Flow

The subcutaneous tissue around your abdomen has excellent vascularization. When you inject semaglutide here, it's absorbed into the bloodstream efficiently and predictably. This means:

• More consistent drug levels throughout the week
• Reliable therapeutic effect
• Predictable appetite suppression

Adequate Fat Layer

The abdomen typically has a sufficient subcutaneous fat layer for proper injection depth. Semaglutide needs to be deposited in this fat layer—not in muscle—for correct absorption kinetics.

Easy Self-Administration

You can easily see and access your abdomen, making proper technique straightforward. The upper arm, by contrast, requires a mirror or assistance.

Step-by-Step: How to Inject Semaglutide in the Abdomen

Step 1: Gather Supplies

• Semaglutide pen (at room temperature for 30 minutes if refrigerated)
• New pen needle (never reuse needles)
• Alcohol swab
• Sharps container for disposal

Step 2: Choose Your Spot

• At least 2 inches (5 cm) away from your belly button
• Avoid areas with scars, bruises, or stretch marks
• Avoid the waistband area (friction can cause irritation)
• Pro tip: Mentally divide your abdomen into quadrants and rotate through them

Step 3: Clean the Area

• Wipe the injection site with an alcohol swab
• Let it dry completely (15-30 seconds)
• Don't blow on it or wave your hand—this recontaminates the area

Step 4: Prepare the Pen

• Attach a new needle
• Prime the pen if it's new (follow pen instructions)
• Dial your prescribed dose

Step 5: Inject

• Pinch a fold of skin (optional with most pen needles, but helps)
• Insert the needle at a 90-degree angle
• Press the injection button and hold
• Count slowly to 10 before removing (ensures complete dose delivery)
• Remove the needle and release the skin fold

Step 6: After the Injection

• Don't rub the site (can affect absorption)
• Remove and dispose of the needle in a sharps container
• Store the pen according to instructions

Site Rotation: Why It Matters and How to Do It

Rotating your injection sites is crucial for long-term semaglutide use. Here's why:

Preventing Lipodystrophy

Injecting in the same spot repeatedly can cause lipodystrophy—changes in the fat tissue that create lumps, dents, or hardened areas. This isn't just cosmetic; it can affect medication absorption.

Reducing Injection Site Reactions

Giving each area time to heal reduces redness, swelling, and discomfort at injection sites.

The Rotation System

Here's a practical rotation approach:

Key rule: Each injection should be at least 1 inch away from your previous injection site.

Alternative Injection Sites: Thigh and Upper Arm

Thigh Injection

The front or outer thigh is a good alternative when:

• Your abdomen is sore from recent injections
• You have extensive abdominal scarring
• You need to give your abdomen extended rest

Technique: Inject into the front or outer middle third of your thigh, halfway between your knee and hip. Avoid the inner thigh (more sensitive, thinner fat layer).

Upper Arm Injection

The back of the upper arm is less commonly used because:

• Difficult to self-administer (can't easily see or reach)
• Often requires someone else to inject
• Thinner fat layer in some people

When it's useful: If you have a partner who can assist with injections, or if abdomen and thigh are both problematic.

Common Injection Mistakes to Avoid

1. Injecting Too Shallow

If the needle doesn't fully penetrate the subcutaneous layer, absorption may be affected. Use the proper angle (90 degrees for most pen needles) and don't be afraid to insert completely.

2. Injecting Into Muscle

If you're very lean with minimal subcutaneous fat, you might accidentally inject into muscle. This can cause:

• Faster absorption than intended
• More pain at the injection site
• Bruising

Solution: Pinch a fold of skin before injecting to ensure you're in the fat layer.

3. Not Waiting Long Enough

The most common mistake: removing the needle before the full dose is delivered. Count slowly to 10 after pressing the injection button. Some pens click when complete—wait for the click.

4. Reusing Needles

Never reuse pen needles. They become dull after one use, increasing pain and infection risk. They can also introduce air bubbles and affect dosing accuracy.

5. Injecting Into Problem Areas

Avoid injecting into:

• Scars or stretch marks
• Bruised or tender areas
• Areas with visible veins
• Sunburned or irritated skin
• Areas with lipodystrophy (lumps or dents)

Managing Injection Site Reactions

Some reaction at injection sites is normal. Here's what to expect and how to manage:

Normal Reactions

• Mild redness: Common, usually fades within hours
• Small bump: May persist for a day or two
• Slight bruising: Occasionally happens, especially if you hit a small blood vessel
• Brief stinging: During injection, should stop quickly

When to Contact Your Provider

• Severe pain, swelling, or redness that worsens over time
• Signs of infection (warmth, pus, fever)
• Allergic reaction (widespread rash, difficulty breathing)
• Hard lumps that don't resolve

Tips to Minimize Reactions

• Let refrigerated pens warm to room temperature before injecting
• Use a new needle every time
• Rotate sites religiously
• Don't inject into irritated areas
• Apply gentle pressure (not rubbing) if you see blood after removing the needle

Frequently Asked Questions

Does it matter what time of day I inject?

Not for injection site effectiveness. Inject at whatever time is most convenient for you to remember. For timing considerations, see our guide on best time to take semaglutide.

Can I inject through clothing?

No. Always inject into clean, bare skin. Injecting through clothing increases infection risk and can affect needle penetration.

What if I see blood after injecting?

A small amount of blood is normal—you may have nicked a tiny blood vessel. Apply gentle pressure with a cotton ball. This doesn't affect the medication's effectiveness.

Can I inject in the same general area each week?

You can stay within the same body region (like abdomen), but move to a different spot within that region each week. Never inject the exact same spot consecutively.

Is it normal for some injections to hurt more than others?

Yes. Nerve distribution varies, so you might occasionally hit a more sensitive spot. The medication temperature, needle quality, and injection speed also affect comfort.