From the Guidelines
Mupirocin is a topical antibiotic that belongs to the monoxycarbolic acid class, with a mechanism of action involving the inhibition of bacterial protein synthesis by binding to bacterial isoleucyl-tRNA synthetase. Its unique mechanism differs from most other antibiotics, making cross-resistance uncommon 1. Mupirocin is primarily effective against gram-positive organisms, particularly Staphylococcus aureus (including MRSA), Streptococcus species, and certain gram-negative organisms. Some key points about mupirocin include:
- It is commonly used to treat impetigo, folliculitis, and small skin infections, and for nasal decolonization of Staphylococcus aureus.
- The typical regimen involves applying the ointment or cream to affected areas 2-3 times daily for 5-10 days.
- For nasal decolonization, the intranasal formulation is applied to each nostril twice daily for 5 days.
- Mupirocin works locally and has minimal systemic absorption, which limits its side effects primarily to local reactions such as burning, stinging, or itching at the application site. As noted in the guidelines for the diagnosis and management of skin and soft tissue infections, mupirocin ointment is recommended for patients with limited number of lesions, particularly for impetigo caused by Staphylococcus and Streptococcus 1. The evidence from these guidelines supports the use of mupirocin as a first-line treatment for certain skin and soft tissue infections, due to its effectiveness and minimal side effects. Overall, mupirocin is a valuable option for the treatment of various skin and soft tissue infections, particularly those caused by gram-positive organisms.
From the FDA Drug Label
Mupirocin inhibits bacterial protein synthesis by reversibly and specifically binding to bacterial isoleucyl transfer-RNA synthetase. The antibiotic class of mupirocin is an antibacterial agent and its mechanism of action (MOA) is the inhibition of bacterial protein synthesis by binding to bacterial isoleucyl transfer-RNA synthetase 2.
- Key points:
- Mupirocin is active against a wide range of gram-positive bacteria
- It is also active against certain gram-negative bacteria
- Mupirocin demonstrates no in vitro cross-resistance with other classes of antimicrobial agents 2.
From the Research
Antibiotic Class and Mechanism of Action of Mupirocin
- Mupirocin is a topical antibacterial agent that inhibits bacterial protein and RNA synthesis 3, 4
- It works by reversibly inhibiting isoleucyl-transfer RNA, thereby inhibiting bacterial protein and RNA synthesis 4, 5
- Mupirocin has excellent in vitro activity against staphylococci and most streptococci, but has less activity against other Gram-positive and most Gram-negative bacteria 3, 4
Unique Features of Mupirocin
- Mupirocin is a polyketide antibiotic produced by Pseudomonas fluorescens 5
- The biosynthetic pathway of mupirocin belongs to the trans-AT group, which is unique among type I polyketide synthases 5
- Mupirocin has a novel chemical structure, which makes cross-resistance less likely to occur than with other currently available topical antibacterial agents 3
Clinical Use of Mupirocin
- Mupirocin is effective in treating primary and secondary superficial skin infections, including impetigo and infected wounds 3, 4, 6
- It is also effective in eradicating nasal carriage of Staphylococcus aureus, including methicillin-resistant forms 3, 4
- Mupirocin has been shown to be as effective as oral erythromycin therapy in treating impetigo 6