Can two people share one peptide vial?

No. The CDC injection-safety rule is one needle, one syringe, only one time, and it specifically says never to draw from a shared vial with a needle or syringe that has already been used on anyone. A fresh needle into a vial someone else already used does not make that vial a community bottle. This site does not publish a shared-vial protocol. Bacteriostatic water's preservative is not a license to share. Full walkthrough at /injecting.

Full injecting guide: sites, needles, rotation, safety

Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use.

Part of injecting: sites, needles and safety. Subcutaneous vs intramuscular, site rotation, lipohypertrophy, needle length and gauge, vial hygiene at injection time, travel syringes, scar tissue, and when to stop and see a clinician. Full walkthrough at /injecting.