Mupirocin

Mupirocin ointment is indicated for the topical treatment of impetigo due to susceptible isolates of Staphylococcus aureus (S. aureus) and Streptococcus pyogenes (S. pyogenes). Mupirocin ointment is an RNA synthetase inhibitor antibacterial indicated for the topical treatment of impetigo due to susceptible isolates of Staphylococcus aureus and Streptococcus pyogenes. ( 1 )

Each gram of Mupirocin Ointment USP contains 20 mg mupirocin, USP in a water-miscible ointment base supplied in 15-gram and 22-gram tubes.

• Ointment: Each gram contains 20 mg mupirocin, USP in a water-miscible ointment base supplied in 15-gram and 22-gram tubes. ( 3 )

Mupirocin ointment is contraindicated in patients with known hypersensitivity to mupirocin or any of the excipients of mupirocin ointment.

• Known hypersensitivity to mupirocin or any of the excipients of mupirocin ointment. ( 4 )

• Severe Allergic Reactions: Anaphylaxis, urticaria, angioedema, and generalized rash have been reported in patients treated with formulations of mupirocin, including mupirocin ointment. ( 5.1 )
• Eye Irritation: Avoid contact with eyes. ( 5.2 )
• Local Irritation: Discontinue in the event of sensitization or severe local irritation. ( 5.3 )
• Clostridium difficile -Associated Diarrhea (CDAD): If diarrhea occurs, evaluate patients for CDAD. ( 5.4 )
• Potential for Microbial Overgrowth: Prolonged use may result in overgrowth of nonsusceptible microorganisms, including fungi. ( 5.5 )
• Risk Associated with Mucosal Use: Mupirocin ointment is not formulated for use on mucosal surfaces. A separate formulation, mupirocin nasal ointment, is available for intranasal use. ( 5.6 )
• Risk of Polyethylene Glycol Absorption: Mupirocin ointment should not be used where absorption of large quantities of polyethylene glycol is possible, especially if there is evidence of moderate or severe renal impairment. ( 5.7 )
• Risk Associated with Use at Intravenous Sites: Mupirocin ointment should not be used with intravenous cannulae or at central intravenous sites because of the potential to promote fungal infections and antimicrobial resistance. ( 5.8 )

5.1 Severe Allergic Reactions Systemic allergic reactions, including anaphylaxis, urticaria, angioedema, and generalized rash, have been reported in patients treated with formulations of mupirocin, including mupirocin ointment [see Adverse Reactions ( 6.2 )].

5.2 Eye Irritation Avoid contact with the eyes. In case of accidental contact, rinse well with water.

5.3 Local Irritation In the event of a sensitization or severe local irritation from mupirocin ointment, usage should be discontinued, and appropriate alternative therapy for the infection instituted.

5.4 Clostridium difficile -Associated Diarrhea Clostridium difficile -associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin-producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibacterial drug use. Careful medical history is necessary since CDAD has been reported to occur over 2 months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibacterial drug use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibacterial treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated.

5.5 Potential for Microbial Overgrowth As with other antibacterial products, prolonged use of mupirocin ointment may result in overgrowth of nonsusceptible microorganisms, including fungi [see Dosage and Administration ( 2 )].

5.6 Risk Associated with Mucosal Use Mupirocin ointment is not formulated for use on mucosal surfaces. Intranasal use has been associated with isolated reports of stinging and drying. A separate formulation, mupirocin nasal ointment, is available for intranasal use.

5.7 Risk of Polyethylene Glycol Absorption Polyethylene glycol can be absorbed from open wounds and damaged skin and is excreted by the kidneys. In common with other polyethylene glycol-based ointments, mupirocin ointment should not be used in conditions where absorption of large quantities of polyethylene glycol is possible, especially if there is evidence of moderate or severe renal impairment.

5.8 Risk Associated with Use at Intravenous Sites Mupirocin ointment should not be used with intravenous cannulae or at central intravenous sites because of the potential to promote fungal infections and antimicrobial resistance.

The following adverse reactions are discussed in more detail in other sections of the labeling:

• Severe Allergic Reactions [see Warnings and Precautions ( 5.1 )]
• Eye Irritation [see Warnings and Precautions ( 5.2 )]
• Local Irritation [see Warnings and Precautions ( 5.3 )]
• Clostridium difficile -Associated Diarrhea [see Warnings and Precautions ( 5.4 )]
• The most frequent adverse reactions (at least 1%) were burning, stinging or pain, and itching. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Glenmark Pharmaceuticals Inc., USA at 1 (888) 721-7115 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice. The following local adverse reactions were reported by at least 1% of subjects in connection with the use of mupirocin ointment in clinical trials: burning, stinging, or pain in 1.5% of subjects; itching in 1% of subjects. Rash, nausea, erythema, dry skin, tenderness, swelling, contact dermatitis, and increased exudate were reported in less than 1% of subjects.

6.2 Postmarketing Experience In addition to adverse reactions reported from clinical trials, the following reactions have been identified during postmarketing use of mupirocin ointment. Because they are reported voluntarily from a population of unknown size, estimates of frequency cannot be made. These reactions have been chosen for inclusion due to a combination of their seriousness, frequency of reporting, or potential causal relationship to mupirocin ointment. Immune System Disorders Systemic allergic reactions, including anaphylaxis, urticaria, angioedema, and generalized rash [see Warnings and Precautions ( 5.1 )] .

8.1 Pregnancy Risk Summary There are insufficient human data to establish whether there is a drug-associated risk with mupirocin ointment in pregnant women. Systemic absorption of mupirocin through intact human skin is minimal following topical administration of mupirocin ointment [see Clinical Pharmacology ( 12.3 )] . No developmental toxicity was observed in rats or rabbits treated with mupirocin subcutaneously during organogenesis at doses of 160 or 40 mg per kg per day, respectively (22 and 11 times the human topical dose based on calculations of dose divided by the entire body surface area). The estimated background risk of major birth defects and miscarriages for the indicated population is unknown. The estimated background risk in the U.S. general population of major birth defects is 2% to 4% and of miscarriage is 15% to 20% of clinically recognized pregnancies. Data Animal Data: Developmental toxicity studies have been performed with mupirocin administered subcutaneously to rats and rabbits at doses up to 160 mg per kg per day during organogenesis. This dose is 22 and 43 times, respectively, the human topical dose (approximately 60 mg mupirocin per day) based on calculations of dose divided by the entire body surface area. Maternal toxicity was observed (body weight loss/decreased body weight gain and reduced feeding) in both species with no evidence of developmental toxicity in rats. In rabbits, excessive maternal toxicity at the high dose precluded the evaluation of fetal outcomes. There was no developmental toxicity in rabbits at 40 mg per kg per day, 11 times the human topical dose based on calculations of dose divided by the entire body surface area. Mupirocin administered subcutaneously to rats in a pre-and postnatal development study (dosed during late gestation through lactation) was associated with reduced offspring viability in the early postnatal period at a dose of 106.7 mg per kg, in the presence of injection site irritation and/or subcutaneous hemorrhaging. This dose is 14 times the human topical dose based on calculations of dose divided by the entire body surface area. The no-observed adverse effect level in this study was 44.2 mg per kg per day, which is 6 times the human topical dose.

8.2 Lactation Risk Summary It is not known whether mupirocin is present in human milk, has effects on the breastfed child, or has effects on milk production. However, breastfeeding is not expected to result in exposure of the child to the drug due to the minimal systemic absorption of mupirocin in humans following topical administration of mupirocin ointment [see Clinical Pharmacology ( 12.3 )] . The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for mupirocin ointment and any potential adverse effects on the breastfed child from mupirocin ointment or from the underlying maternal condition. Clinical Considerations To minimize oral exposure of the drug to children, a breast and/or nipple being treated with mupirocin ointment should be thoroughly washed prior to breastfeeding.

8.4 Pediatric Use The safety and effectiveness of mupirocin ointment have been established in the age range of 2 months to 16 years. Use of mupirocin ointment in these age-groups is supported by evidence from adequate and well-controlled trials of mupirocin ointment in impetigo in pediatric subjects studied as a part of the pivotal clinical trials [see Clinical Studies ( 14 )] .

Mupirocin is an RNA synthetase inhibitor antibacterial [see Microbiology ( 12.4 )].