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Peptide Injection Guide

Most peptides are injected subcutaneously (SubQ) — into the fat layer just beneath the skin. It's simpler, less painful, and equally effective for most compounds.

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Needle Selection

SubQ (subcutaneous — into fat layer): • 31 gauge × 8mm (5/16") insulin needle — ideal for belly/love handles • 31 gauge × 6mm — for leaner individuals • 1mL/100-unit insulin syringe IM (intramuscular — into muscle): • 25 gauge × 1" — glutes • 27 gauge × 0.5" — delts, quads • Not needed for most peptides unless specifically indicated (Thymalin, NAD+ IM)
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SubQ Injection Technique

Step 1: Wash hands. Wipe injection site with alcohol swab. Let dry 30 seconds. Step 2: Pinch 1-2 inches of fat between thumb and index finger (belly fat, love handles, or upper thigh). Step 3: Insert needle at 45–90 degrees depending on site. 45° for lean individuals, 90° for more fat. Step 4: Release the pinch (don't inject into a pinched fold). Step 5: Inject slowly and steadily. Don't rush. Step 6: Remove needle and apply gentle pressure with alcohol swab. Don't rub.
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Injection Sites and Rotation

Primary SubQ sites: • Lower abdomen (2 inches from navel) — most common • Love handles / flanks • Upper thigh • Upper outer arm Rotation rule: Move at least 1-2cm from previous injection. Keep a mental map or written log. Repeated injection in the same spot causes: • Lipodystrophy (fat tissue damage) • Scar tissue • Reduced absorption • Lumps
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Dealing With Injection Pain

Some peptides sting more than others: • GHK-Cu: stings significantly — hyperdilute with more BAC water (5–10mL) • LL-37: can cause notable site pain — ice before injection helps • NAD+: burn if injected too fast — inject slowly over 3–5 min per mL • Most peptides: minimal discomfort with proper technique Pre-injection ice for 60 seconds reduces sensation. Allow refrigerated peptides to warm to room temp before injecting.

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