An FDA Reversal on Peptides Could Open the Market to Unsafe Drugs ProPublica Are Peptides Safe? The Clinical Reality, Are peptides safe? The answer starts with clinical medicine: most are not FDA approved and are often sold as research chemicals, with real quality, purity, Public advisory Think twice before injecting peptides bought online: unauthorized products can seriously harm you RFK Jr. promotes peptides. Now the FDA weighs easing limits on the unproven chemicals