The Bioavailability Challenge for Oral Peptides
Most peptides are poorly absorbed orally because stomach acid and digestive enzymes degrade them before they reach systemic circulation. The peptide bonds that give these compounds their biological activity are the same bonds that digestive proteases target. This is why most therapeutic peptides are administered by injection.
Exceptions: When Oral Works
BPC-157 is unusual among therapeutic peptides in that it appears to be effective via oral administration in animal studies, possibly because its mechanism of action in the GI tract does not require systemic circulation. Oral BPC-157 formulations are used by physicians for gastrointestinal applications specifically. For systemic tissue repair, injectable formulations are typically preferred.
GHK-Cu: Topical Is Legitimate
GHK-Cu is one of the few therapeutic peptides where topical application has genuine research support for skin applications. The small tripeptide structure allows sufficient skin penetration for local effects. Topical is not equivalent to systemic administration but is appropriate for skin-specific goals.
Physician Guidance on Route
The appropriate administration route depends on the specific peptide, the clinical goal, and patient factors including comfort with injections. Your physician will recommend the most appropriate route for your specific situation — this is not a decision to make independently based on convenience alone.