Mupirocin

Mupirocin (2%)

Composition

Mupirocin is a topical antibiotic cream or ointment, typically available in a 2% concentration. It is synthesized from a strain of the bacterium Pseudomonas fluorescens. Generic formulations of mupirocin may vary slightly in inactive ingredients, which can include emulsifiers, preservatives, and skin conditioning agents.

Mechanism of Action

Mupirocin works by inhibiting bacterial protein synthesis. It binds specifically to isoleucyl-tRNA synthetase, an enzyme critical for protein formation in bacteria. This action hinders the ability of bacteria to synthesize proteins effectively, leading to the cessation of bacterial growth and eventual cell death. Mupirocin is primarily effective against Gram-positive bacteria, including Staphylococcus aureus (including MRSA) and Streptococcus species.

Dosage

The standard dosage for mupirocin ointment (2%) varies depending on the condition being treated, but general guidelines include:

• For Localized Skin Infections: Apply a small amount to the affected area 2 to 3 times daily for up to 10 days.
• For Impetigo: Apply mupirocin ointment directly to the infected skin area 3 times a day for 5 to 10 days.
• Always follow the specific guidance provided by a healthcare professional.

Usage

Mupirocin is used clinically for:

• Treatment of skin infections caused by susceptible bacteria, such as impetigo, folliculitis, or infected eczema.
• Nasal mupirocin (intranasal formulation) is used to eliminate nasal carriage of Staphylococcus aureus, particularly in MRSA carriers.
• Mupirocin should be applied only to the skin and not to deeper wounds or burns.

Side Effects

Common side effects of mupirocin can include:

• Localized irritation, burning or stinging sensation at the application site.
• Rash or allergic reactions (though less common).
• Prolonged use may lead to the development of antibiotic-resistant bacteria.

Severe side effects are rare, but if symptoms such as severe skin rash, difficulty breathing, or swelling occur, immediate medical attention should be sought.

Recommendations

• Always use mupirocin as prescribed by a healthcare provider.
• Clean and dry the affected area before applying mupirocin.
• Avoid occlusive dressings unless directed, as this may increase absorption and irritation.
• Wash hands before and after application to prevent spreading the infection.
• Do not use mupirocin in the eyes, nose, or mouth without specific instruction.

Important Note

Mupirocin should not be used for viral infections (like the common cold or flu) and is not intended for long-term or preventative use without medical advice. Patients should inform their healthcare provider of any allergies or other medications they are taking, as mupirocin may interact with certain treatments. Avoid concurrent use of other topical agents on the same area unless directed by a healthcare provider. For any persistent or worsening symptoms, consult a healthcare professional