Bactrocin

A. Approved Indications

• Topical Treatment of Impetigo:
  Caused by Staphylococcus aureus and Streptococcus pyogenes
• Treatment of Secondary Skin Infections:
  Including infected eczema, folliculitis, minor burns, and traumatic skin lesions
• Nasal Decolonization of Methicillin-resistant Staphylococcus aureus (MRSA):
  For intranasal use in adult and pediatric patients to eliminate nasal carriage of MRSA

B. Off-label / Clinically Accepted Uses

• Prevention of Post-surgical Wound Infections:
  Intranasal mupirocin to reduce surgical site infections in MRSA carriers
• Treatment of Infected Atopic Dermatitis (localized)
• Adjunct in Eradication of MRSA in Decolonization Protocols:
  Combined with chlorhexidine body wash

Route of Administration:

• Topical (Dermal)
• Intranasal (Nasal Mucosa)

Available Formulations in Bangladesh (per Medex.com.bd):

• Cream: 2% (20 mg/g)
• Ointment: 2% (20 mg/g)
• Nasal ointment: 2% in white soft paraffin base

Adults and Children:

• Impetigo or Minor Skin Infections:
  Apply a small amount of 2% ointment or cream to the affected area three times daily for 5 to 10 days.
  May cover with gauze if needed.
• Nasal MRSA Colonization:
  Apply a small amount of 2% nasal ointment into each nostril twice daily for 5 days.
  Patients should press both sides of the nose to spread the ointment evenly.

Pediatrics (≥2 months):

• Same dosing as adults for both topical and intranasal use.

Geriatrics:

• No dosage adjustment required.

Renal/Hepatic Impairment:

• No dosage adjustment necessary for short-term topical use.

Administration Instructions:

• For external use only; avoid contact with eyes, mouth, or open mucosa (except for nasal formulation).
• Wash hands before and after application.
• Discontinue if severe irritation or sensitization occurs.

Mupirocin acts by inhibiting bacterial isoleucyl-tRNA synthetase, an essential enzyme involved in bacterial protein synthesis. By preventing the incorporation of isoleucine into bacterial proteins, mupirocin halts bacterial growth. This action is bacteriostatic at low concentrations and bactericidal at high concentrations, particularly effective against Staphylococcus aureus (including MRSA) and Streptococcus pyogenes. Its mechanism is unique among topical antibiotics, minimizing cross-resistance.

• Absorption (Topical):
  Systemic absorption through intact skin is minimal.
• Distribution:
  Primarily remains localized at the site of application.
• Metabolism:
  If absorbed, rapidly hydrolyzed to inactive metabolite monic acid.
• Elimination:
  Excreted via kidneys as monic acid if systemically absorbed.
• Half-life:
  Not applicable due to minimal systemic exposure.
• Onset of Action:
  Clinical improvement typically noted within 1 to 3 days of treatment.

• Pregnancy:
• Former FDA Category B
• Animal studies have shown no fetal harm; human data are limited
• Use only if clearly needed
• Lactation:
• Generally considered safe for use during breastfeeding
• Avoid direct application to the nipple area
• If necessary, cleanse the skin thoroughly before nursing
• Recommendation:
• Use with caution during pregnancy and lactation, especially in large quantities or on broken skin

• Primary Therapeutic Class: Topical Antibiotic
• Subclass: Protein synthesis inhibitor (Isoleucyl-tRNA synthetase inhibitor)

• Known hypersensitivity to mupirocin or any component of the formulation
• Application to large open wounds or burns due to increased risk of systemic absorption and polyethylene glycol toxicity (for ointment formulation containing PEG)
• Intranasal use of non-nasal mupirocin products

• Systemic Absorption Risk:
  Avoid large-surface application, especially in patients with renal impairment (due to PEG accumulation)
• Hypersensitivity Reactions:
  May cause contact dermatitis, allergic reactions, or anaphylaxis
• Superinfection:
  Prolonged use may result in fungal or bacterial superinfection
• Clostridioides difficile-associated Diarrhea (rare):
  Discontinue use if significant diarrhea develops
• Resistance Development:
  Limit use to indicated conditions to reduce the risk of resistance

Common:

• Dermatologic:
  Burning, stinging, itching, dryness, rash at the application site
• Nasal Use:
  Headache, rhinitis, pharyngitis, cough, taste disturbance

Less Common:

• Erythema, contact dermatitis, local edema

Serious (Rare):

• Anaphylaxis or severe allergic reactions
• Superinfection including resistant organisms
• Localized severe irritation or ulceration

Timing:

• Most reactions occur early and are self-limiting; discontinue if symptoms persist or worsen

• Topical Use:
  Clinically significant drug interactions are not expected due to minimal systemic absorption
• Nasal Use (in MRSA protocols):
  May be combined with systemic antibiotics or antiseptic washes (e.g., chlorhexidine), with no interaction reported
• Enzyme Involvement:
  Not metabolized via CYP450 system
• Drug-Food/Alcohol:
  No interactions known

• CDC & WHO MRSA Decolonization Protocols (2023):
  Mupirocin remains a key component of nasal decolonization strategies for MRSA in both community and healthcare settings.
• UK NICE Guidance (2022):
  Recommends mupirocin for limited periods in confirmed or high-risk MRSA nasal carriers preoperatively.
• Resistance Surveillance (2023):
  Reports of mupirocin resistance are increasing, particularly with prolonged or repeated use—guidelines now emphasize short-course and targeted use.

• Temperature: Store below 25°C (77°F)
• Humidity: Keep tightly closed to protect from excessive moisture
• Light Protection: Store in original packaging, away from direct light
• Handling Instructions:
• Do not freeze
• Do not use past expiration date
• For single-patient use only (especially nasal formulation)
• Discard unused portion after the treatment course