Subcutaneous (SubQ) injection is the most common administration route for research peptides. Proper technique minimizes discomfort, reduces bruising, and ensures consistent absorption. This guide covers everything from syringe selection to post-injection care.
Syringe Selection
Use a 29–31 gauge, 0.5-inch (12.7mm) insulin syringe for all SubQ peptide injections. The 100-unit (1mL) format is standard. Finer gauges (31G) cause less discomfort but are more prone to bending. 29G is the best balance of comfort and durability. Never reuse syringes — the needle dulls immediately after first use.
Injection Sites
Preferred sites in order: 1) Abdomen (2 inches from navel, avoid the navel itself), 2) Outer thigh (middle third), 3) Upper arm (posterior, outer surface). Rotate sites systematically — never inject the same spot twice in a row. Consistent rotation prevents lipohypertrophy (fatty lumps from repeated injections).
Injection Technique
Clean the site with an alcohol swab and allow to dry completely (wet alcohol stings). Pinch a fold of skin between thumb and forefinger. Insert the needle at a 45-degree angle for lean individuals, or 90 degrees if there is adequate subcutaneous fat. Inject slowly and steadily — do not rush. Withdraw the needle at the same angle as insertion. Apply gentle pressure with a clean swab — do not rub, as rubbing can disperse the compound unevenly.
Common Mistakes
Injecting into muscle: If you hit muscle (sharp, deep pain), withdraw and re-inject with a shallower angle. Air bubbles: Small air bubbles in SubQ injections are harmless — only IV injections require complete air removal. Leakage: If solution leaks back out, the needle was withdrawn too quickly. Hold for 5 seconds after injection before withdrawing.