Mupirocin is a topical antibiotic that was originally isolated from Pseudomonas fluorescens. The drug is bacteriostatic at low concentrations and bactericidal at high concentrations, and is most effective against Gram-positive bacteria. Mupirocin works unlike other antibiotics in that it binds selectively to bacterial isoleucyl-tRNA synthetase, thereby stopping the incorporation of isoleucine into bacterial proteins and blocking further synthesis of those proteins. Mupirocin’s unique mechanism of action means that the drug may be effective against organisms that are resistant to other antibiotics.1 The drug is used to treat infections caused by Gram-positive bacteria, such as those seen in furuncle, impetigo, and eczema, and is also used to combat methicillin-resistant Staphylococcus aureus (MRSA) and other resistant bacteria.
Mupirocin should not be used for extended lengths of time in order to preserve its effectiveness against resistant bacteria, and is not effective against most anaerobic bacteria, yeasts, and fungi.
For more information, including a MSDS sheet, please see PNA’sMupirocin page.
Skin Infections: Mupirocin is the topical treatment of choice against impetigo caused by Staphylococcus aureus and Streptococcus pyogenes, and may be preferred over systemic treatments of the infection. The drug is also indicated for use in other skin infections, such as eczema, folliculitis, furunculosis, atopic dermatitis, and epidermolysis bullosa, as well as wounds, burns, and ulcers.
Nasal Carriage of Staphylococcus aureus: Mupirocin is also effective in temporary removal of MRSA and other resistant bacteria in the nasal carriage, thereby preventing an outbreak of MRSA infections in susceptible populations.
Serious side effects are not expected with topical mupirocin therapy. Common side effects in patients taking mupirocin include:
Burning, stinging or irritation of skin
Itching or pain
Rash or dry skin
Tenderness or swelling
Patients who suffer from severity of these common side effects should contact their pharmacist or physician right away. Patients who experience serious allergic reaction (including severe rash, itching, and swelling of the face/tongue/throat, severe dizziness, or trouble breathing) or systemic allergic reaction (including anaphylaxis, urticaria, angioedema and generalized rash) should inform their physician immediately.
Patients who are allergic to mupirocin should not take this drug. Formulations of the drug in polyethylene glycol should not be used in conditions where the drug may be absorbed in large concentrations—such as through burns or open wounds—especially if patient experiences moderate to severe renal impairment.4
Latest News and Research
One of the biggest challenges with MRSA these days is avoiding transmission of the resistant bacteria in cases where patients are particularly vulnerable to infection, such as critical surgeries. The hospital setting has long been a concern because patients often come in carrying MRSA without presenting symptoms of an infection and pass the bacteria on the patients for whom such an infection could be fatal. In an ongoing investigation of how best to reduce risk of infections, scientists have found that treating nasal carriers of MRSA before they undergo cardiothoracic or orthopedic surgeries greatly reduces subsequent infections and in turn, reduces hospital costs.5
Mupirocin may also be effective in short-term treatment of chronic rhinosinusitis in surgically recalcitrant patients.6 It is important to note, however, that a nasal mupirocin wash in these patients can alter the nasal flora, which is important in determining what antibiotic will have maximum efficacy in treating persistent infections.7
“Mupirocin topical Disease Interactions,” December 1, 2015, http://www.drugs.com/disease-interactions/mupirocin-topical.html#Polyethylene_Glycol ↩
“Reduced Costs for Staphylococcus aureus Carriers Treated Prophylactically with Mupirocin and Chlorhexidine in Cardiothoracic and Orthopaedic Surgery,” August 12, 2010, http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0043065 ↩
“A randomized trial of mupirocin sinonasal rinses versus saline in surgically recalcitrant staphylococcal chronic rhinosinusitis,” August 2, 2012, http://onlinelibrary.wiley.com/doi/10.1002/lary.23486/abstract;jsessionid=A3DAB7503A58C568C90123F525A9CAE7.f02t03?userIsAuthenticated=false&deniedAccessCustomisedMessage= ↩
“Changes in Sinus Bacterial Culture Following Mupirocin
Treatment in Surgically Recalcitrant Chronic Rhinosinusitis,” February 2015, http://crawl.prod.proquest.com.s3.amazonaws.com/fpcache/2c1d339bb78ec9c74d022618b79c7a76.pdf?AWSAccessKeyId=AKIAJF7V7KNV2KKY2NUQ&Expires=1452123283&Signature=tM0CvjJPctAbfdq0zaK6vFAKSME%3D ↩