What is the use of Mupirocin (Bactroban)?

From the Guidelines

Mupirocin should be used as a 2% ointment or cream applied to the affected area three times daily for 5-10 days for the treatment of bacterial skin infections, particularly those caused by Staphylococcus aureus, including methicillin-resistant strains (MRSA). When considering decolonization strategies, nasal decolonization with mupirocin twice daily for 5–10 days, in conjunction with topical body decolonization regimens with a skin antiseptic solution (eg, chlorhexidine) for 5–14 days or dilute bleach baths, may be effective in preventing recurrent infections 1. The use of mupirocin for decolonization has been shown to reduce the prevalence of nasal colonization and the number of cases of recurrent skin and soft tissue infections (SSTI) 1. However, it is essential to note that the efficacy of mupirocin in preventing infections among nasal carriers is still unclear, and the development of resistance can occur with prolonged or repeated use 1. Therefore, mupirocin should be used only as prescribed and for the full duration of treatment, and patients should be monitored for signs of resistance or treatment failure. In addition to mupirocin, other decolonization strategies, such as the use of chlorhexidine soap and dilute bleach baths, may also be effective in preventing recurrent infections 1. Overall, the use of mupirocin, in conjunction with other decolonization strategies and hygiene measures, may be an effective approach in preventing recurrent bacterial skin infections, particularly those caused by MRSA. Key points to consider when using mupirocin include:

• Apply 2% ointment or cream to the affected area three times daily for 5-10 days
• Use nasal decolonization with mupirocin twice daily for 5–10 days, in conjunction with topical body decolonization regimens
• Monitor for signs of resistance or treatment failure
• Use in conjunction with other decolonization strategies, such as chlorhexidine soap and dilute bleach baths
• Emphasize the importance of hygiene measures, such as covering infected skin and draining wounds, and avoiding sharing of personal items.

From the FDA Drug Label

Application of 14C-labeled mupirocin ointment to the lower arm of normal male subjects followed by occlusion for 24 hours showed no measurable systemic absorption (<1. 1 nanogram mupirocin per milliliter of whole blood). The pharmacokinetics of mupirocin has not been studied in individuals with renal insufficiency

• Mupirocin is an antibacterial agent with a unique mode of action, inhibiting bacterial protein synthesis by reversibly and specifically binding to bacterial isoleucyl transfer-RNA synthetase.
• Systemic absorption of mupirocin is minimal, with no measurable absorption (<1.1 nanogram mupirocin per milliliter of whole blood) after topical application.
• The elimination half-life of mupirocin is 20 to 40 minutes after intravenous administration, but its pharmacokinetics in individuals with renal insufficiency is unknown 2.

From the Research

Mupirocin Overview

• Mupirocin is a novel antibiotic used for topical application only, with a unique chemical structure and mode of action distinct from other antibacterial agents 3.
• It is effective against a wide range of Gram-positive bacteria, including staphylococci and most streptococci, and moderately active against Gram-negative bacteria 3, 4.

Efficacy in Skin Infections

• Mupirocin 2% ointment has demonstrated efficacy in treating primary and secondary skin infections, with over 90% of patients achieving clinical cure or improvement 3, 4.
• It has been shown to be effective in eradicating bacterial pathogens, including Staphylococcus aureus, in over 90% of patients 3, 4.
• Mupirocin has been compared to other topical antibiotics, with similar or superior efficacy in some studies 4, 5.

Nasal Decolonization

• Intranasal 2% mupirocin calcium ointment has been shown to be effective in eradicating nasal carriage of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA) 3, 6.
• A dose-ranging study found that a 10-dose regimen of intranasal mupirocin was superior to a 6-dose regimen in decolonizing S. aureus from the anterior nares 6.
• However, recent studies have raised concerns about the emergence of mupirocin-resistant MRSA strains, which may impact the effectiveness of nasal decolonization protocols 7.

Resistance and Limitations

• The increasing incidence of mupirocin-resistant MRSA strains has been reported, with one study finding that less than 80% of MRSA strains were susceptible to mupirocin 7.
• This has led to suggestions that alternative regimens, such as intranasal povidone iodine, may be preferable for patient decolonization in certain cases 7.