Mupirocin is a topical antibiotic used to treat various skin infections. It is produced by fermentation using the bacterium Pseudomonas fluorescens and is effective against a wide range of bacteria, including Staphylococcus aureus (including methicillin-resistant strains) and Streptococcus pyogenes. Mupirocin works by inhibiting bacterial protein synthesis, thereby preventing bacterial growth. It is commonly used to treat conditions such as impetigo, folliculitis, and furunculosis. The ointment is typically applied to the affected area three times daily for up to 10 days. Common side effects may include burning, stinging, itching, and rash. It is important to avoid using the ointment in the eyes, nose, or mouth, and to discontinue use if a hypersensitivity reaction occurs. As with other antibacterial products, prolonged use may result in overgrowth of non-susceptible organisms, including fungi. Patients should consult with a healthcare provider before using this medication, especially if they are pregnant, breastfeeding, or have kidney problems.