Sources: U.S. Food and Drug Administration (FDA) Compounding and the FDA (503A & 503B guidance) FDA warning letters on unapproved peptide products National Institutes of Health (NIH) PubMed FDA Peptide Update: Category 2 Removals Explained The Peptide Split: How GLP 1s, Lutathera, Vosoritide, and Peptide Cancer Vaccines Are Quietly Rewriting Medicine While BPC 157, TB 500, MOTS c, and the Wellness Grift Borrow Their Halo They Call It the 'Wolverine Peptide.' And Everyone from Biohackers to Your Dad Wants It Now.