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 The FDA's Current Position on Peptides Explained Holt Law The Peptide Boom Is Getting Out of Hand The Atlantic Unauthorized injectable peptide drugs seized and sold by Canada Peptide may pose serious health risks Canada.ca