Side-by-Side Comparison · 2026

Gramicidin S vs Polymyxin B

Gramicidin S vs Polymyxin B — mechanism, half-life, dosing, and research status compared. Which is right for your protocol?

Gramicidin S
Antimicrobial Peptide

Gramicidin S (Soviet gramicidin) is a cyclic decapeptide antibiotic discovered in 1942 by Soviet scientists Gause and Brazhnikova from Bacillus brevis, during World War II. It became a frontline topical wound antiseptic for Soviet forces....

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Polymyxin B
Antimicrobial Peptide

Polymyxin B is a cyclic lipopeptide antibiotic from Bacillus polymyxa that was approved in the 1960s and fell out of favor due to nephrotoxicity, but has experienced a major clinical resurgence as a last-resort treatment for carbapenem-resistant Gram-negative infections (Acinetob...

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Key Parameters
Parameter Gramicidin S Polymyxin B
Category Antimicrobial Peptide Antimicrobial Peptide
Research Approved (topical, certain countries) FDA Approved
Half-Life Hours (topical) 6-8 hours
Typical Dose 0.1-0.5% in topical preparations 15,000-25,000 units/kg/day IV
Frequency As needed Every 12 hours IV
Route Topical IV / IM / Topical / Intrathecal
FDA Status Not FDA approved (approved in USSR/Russia, used in Europe) Approved (systemic Gram-negative infections)

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Frequently Asked Questions
What is the difference between Gramicidin S and Polymyxin B?
Gramicidin S: Gramicidin S (Soviet gramicidin) is a cyclic decapeptide antibiotic discovered in 1942 by Soviet scientists Gause and Brazhnikova from Bacillus brevis, during World War II. It became a frontline topic... Polymyxin B: Polymyxin B is a cyclic lipopeptide antibiotic from Bacillus polymyxa that was approved in the 1960s and fell out of favor due to nephrotoxicity, but has experienced a major clinical resurgence as a l...
Which has a longer half-life, Gramicidin S or Polymyxin B?
Gramicidin S half-life: Hours (topical). Polymyxin B half-life: 6-8 hours.
Can you stack Gramicidin S and Polymyxin B?
Gramicidin S and Polymyxin B are in the same category and used together in research protocols. Always consult relevant literature and follow appropriate guidelines.

For research use only. Not medical advice. ASCEND does not conduct or endorse any specific research protocol. Always consult relevant scientific literature and regulatory guidelines.