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Basics & Technique

Where do I inject, and how do I rotate sites?

Updated 2026-05-03

Most peptides go into the soft fatty layer under your skin. The easiest spots are the lower belly (about 2 inches from your belly button), the front and outer thighs, and the back of the upper arms. Use at least 4 to 6 different sites and move at least 1 inch from your last injection. Hitting the same spot every day builds up scar tissue, which causes lumps and uneven absorption over time.

IfIf you are doing daily injections
Thenthen run a 6-day rotation - left belly, right belly, left thigh, right thigh, left arm, right arm, then start over
IfIf you are doing weekly GLP-1 injections
Thenthen alternate between belly and thigh each week - even weekly use can build a small lump if you stay in one spot
IfIf a hard lump forms at an old site
Thenthen stop using that area for 2 to 4 weeks and rotate elsewhere - most lumps resolve on their own
IfIf you have very little belly fat
Thenthen pinch the skin and inject at a 45 degree angle instead of 90, or move to the thigh where there is more cushion
Key facts
  • Subcutaneous injection means the medicine goes into the fatty tissue between skin and muscle
  • Avoid the inner thigh - more blood vessels and nerves than the front or outer thigh
  • Stay at least 2 inches from your belly button and avoid moles, scars, or bruised skin
  • Repeated injections in the same spot cause lipohypertrophy (fatty lumps that absorb medicine unevenly)
  • A 29 to 31 gauge insulin needle, half-inch length, works for most peptides and most body types
  • Pinch the skin to make a fold, insert quickly, push the plunger slowly, then withdraw straight
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