Antimicrobial · Investigational
Gramicidin S
No lawful US pathway
01 · Overview
Gramicidin S is a cyclic decapeptide antibiotic consisting of two identical pentapeptide sequences joined in a ring. It kills bacteria by disrupting cell membrane integrity, and its amphipathic beta-sheet conformation favors insertion into lipid bilayers.
It has potent bactericidal activity against Staphylococcus aureus, including methicillin-resistant isolates (PMID 39642693). It is distinct from the linear gramicidin found in some approved topical combination products and is not itself FDA approved.
02 · Research summary & key findings
Gramicidin S has potent activity against methicillin-sensitive and methicillin-resistant Staphylococcus aureus clinical isolates in vitro, but high haemolytic toxicity currently limits its application to topical use (PMID 39642693). Analog programs have made rational modifications to the beta-turn and beta-strand regions aiming to reduce haemolytic and nephrotoxic effects while preserving antibacterial potency, with toxicity assessed in human red blood cells and human embryonic kidney cells (PMID 39642693). No human efficacy trials were identified.
03 · Regulatory status
Gramicidin S is in the investigational stage. While preclinical and early-phase data exist, it has not received regulatory approval for clinical use in the United States.
No lawful pathway today
Gramicidin S is not FDA-approved and does not currently have a lawful prescription or compounding pathway in the United States, so we do not sell it and will not book a consultation for it. That can change: in 2026 FDA began reviewing several peptides for compounding.
See the 3 FDA-approved compounds in Antimicrobial
Tell me if the status changes
One email, only if this compound's regulatory standing actually moves. Not a newsletter, not a sales sequence.
04 · Administration routes
- Topical
References
- [1]Expanding the therapeutic window of gramicidin S towards a safe and effective systemic treatment of methicillin-resistant S. aureus infections Eur J Med Chem, 2025. PMID 39642693
Primary literature
- PubMed: "Gramicidin S"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov: "Gramicidin S"
Registered interventional and observational studies, including status and phase.
- PubChem: "Gramicidin S"
Chemical structure, molecular properties, and bioactivity data.
Related peptides in Antimicrobial
Disclaimer: This information is provided for educational and research purposes only. It is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting any peptide therapy. The Peptide Association does not endorse or recommend any specific treatment protocol. See our editorial policy for how this content is produced and reviewed. Clinicians: join the network.