Injection site rotation
Eight viable sites, eight weeks in your rotation. Why bother? Because reusing the same area creates harder bumps under the skin (lipohypertrophy) that absorb medication unevenly. Rotation is the simplest way to keep absorption consistent.
The eight sites
Every GLP-1 medication is given subcutaneously — into the fat layer just under the skin. Three body regions are commonly used:
- Abdomen: four quadrants, each at least 1 inch from your belly button.
- Thighs: front-outer fatty area of each upper thigh.
- Upper arms: back-outer fatty area of each upper arm (you may need help reaching them).
The 8-week cycle
A common pattern is to rotate clockwise through all 8 sites, one per week. That gives each site 8 weeks of rest before re-use — well past the 2-week minimum that most prescribing labels suggest.
Technique basics
- Wash your hands. Wipe the site with an alcohol pad and let it air-dry — wet alcohol stings.
- Pinch the skin loosely between thumb and forefinger to lift the fat layer.
- Hold the auto-injector flush against the skin and press the activation button.
- Hold for the count specified by your pen (typically 5-10 seconds) so the full dose delivers.
- Release the pinch and the pen. Press a clean tissue against the site if there is bleeding; do not rub.
Sites to avoid
- Tattoos, scars, moles, irritated skin, bruised areas.
- Skin that is hard or lumpy from previous injections.
- The exact area around your belly button (most labels say stay 1 inch away).
- Stretch marks where the skin layer is unusual.
If a site reacts
A small amount of redness, mild itching, or a small lump that fades within a day or two is common and not a concern. Persistent lumps, hard knots, significant swelling, hives, or systemic symptoms (fever, widespread rash) warrant calling your prescriber.
Tracking rotation
The GLP1 Base iOS app maps your last 8 shots across the 8 sites and highlights which sites are due for use and which are still recovering — so you stop having to remember.