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Tyrothricin

Peptide

Tyrothricin is a cyclic peptide antibiotic complex from Bacillus brevis - the first peptide antibiotic used in humans (1939). Contains 60-80% tyrocidine (cyclic decapeptides) and 20-40% gramicidin (linear peptides). Over 60 years of clinical use with no significant resistance reported. RCT (DoriPha, n=321): Tyrothricin lozenges showed 64% improved complete remission vs placebo at 72 hours for acute pharyngitis. Used topically for sore throat, skin infections. SAFETY CONCERN: Systemic toxicity limits to topical/local use only.

Quick Answer

What it is

Tyrothricin is a cyclic peptide antibiotic complex from Bacillus brevis - the first peptide antibiotic used in humans (1939). Contains 60-80% tyrocidine (cyclic decapeptides) and 20-40% gramicidin (linear peptides).

Key findings

  • Grade A: Acute Pharyngitis (Respiratory Health)
  • Grade A: Antimicrobial Resistance (Respiratory Health)
  • Grade A: Systemic Toxicity (General Health)

Safety

  • SAFETY CONCERN: Systemic toxicity limits to topical/local use only.
  • SAFETY CONCERN: Systemic administration causes significant toxicity - hemolysis and nephrotoxicity.
  • Similar toxicity profile to component gramicidin.
⚠️ Research Notice

This peptide information is for educational and research purposes only. Peptides may not be FDA-approved for human use and may only be legally available for research purposes. Consult qualified healthcare professionals before considering any peptide compounds.

ℹ️ Quick Facts: Tyrothricin

Quick Facts: Tyrothricin

  • Best Evidence:Grade A
  • Conditions Studied:3
  • Research Outcomes:6
  • Grade A Findings:3
  • Grade B Findings:2
  • Key Effect:Respiratory Health
A3
B2
C1
D0
3 conditions · 6 outcomes

Detailed Outcomes

|
A
Acute Pharyngitis
DoriPha RCT (n=321): Tyrothricin/benzocaine/benzalkonium lozenges showed 64% improved complete remission vs placebo at 72 hours. Rapid analgesic effect. Effective for severe throat pain and difficulty swallowing.
moderate↑Improves
A
Antimicrobial Resistance
Decade-long surveillance: No significant resistance development after 60+ years of clinical use. Multiple mechanisms in peptide mixture prevent single-step resistance. Unique resistance profile among antibiotics.
large↑Improves
B
Oropharyngeal Infections
Multiple lozenge products (Tyrozets, Lemocin, Dorithricin, Anginovag) for pharyngitis treatment. Combined with local anesthetics and antiseptics. Standard OTC sore throat therapy in many countries.
moderate↑Improves
A
Systemic Toxicity
SAFETY CONCERN: Systemic administration causes significant toxicity - hemolysis and nephrotoxicity. Use restricted to topical and local applications. Similar toxicity profile to component gramicidin.
large↑Worsens
B
Skin Wound Infections
Used for infected superficial and small-area wounds. Broad spectrum gram-positive and antifungal activity. Available in various topical formulations. Long history of safe and effective use.
moderate↑Improves
C
Antimicrobial Activity
9 preclinical studies support this finding. Primarily preclinical evidence.
moderate↑Improves

Research Citations (16)

Electrospun fibers loaded with antimicrobial peptides for treatment of wound infections.
(2022)
PMID: 36150615
Efficacy and safety of a triple active sore throat lozenge in the treatment of patients with acute pharyngitis: Results of a multi-centre, randomised, placebo-controlled, double-blind, parallel-group trial (DoriPha)
(2018)
PMID: 30329199
Tyrothricin--An underrated agent for the treatment of bacterial skin infections and superficial wounds?
(2016)
PMID: 27455547
Chitosan-Based Film of Tyrothricin for Enhanced Antimicrobial Activity against Common Skin Pathogens Including Staphylococcus aureus.
(2016)
PMID: 26907760
Reduction of Inflammatory and Noninflammatory Lesions with Topical Tyrothricin 0.1% in the Treatment of Mild to Severe Acne Papulopustulosa: A Randomized Controlled Clinical Trial.
(2016)
PMID: 26458265
Decade-long use of the antimicrobial peptide combination tyrothricin does not pose a major risk of acquired resistance with gram-positive bacteria and Candida spp
(2015)
PMID: 25985581
Inhibition of malaria parasite blood stages by tyrocidines, membrane-active cyclic peptide antibiotics from Bacillus brevis
(2007)
PMID: 17462586
Tyrocidine B and gramicidin S. Structure and antibacterial action
(1992)
PMID: 1391687
Antibiotics and endodontics.
(1990)
PMID: 2090089
In vitro antibacterial activity of gramicidin and tyrothricin.
(1983)
PMID: 6199032

Related Peptides

Gramicidin

Peptide

2 shared conditions · 8 outcomes

Gramicidin is a cyclic peptide antibiotic from Bacillus brevis, first isolated 1941, FDA-approved 1955 as Neosporin component. Topical use only (lozenges, eye drops, ointments) due to hemolysis. Gramicidin D (mixture of A/B/C) used clinically. Ophthalmic study (n=91): Effective and safe for bacterial corneal ulceration. Combined with polymyxin B and neomycin. One of first membrane-active peptide antibiotics. SAFETY CONCERN: Highly hemolytic - systemic use contraindicated.