Polytracin

Approved Indications:

• Topical treatment of localized superficial skin infections, including:
• Minor cuts, scrapes, and abrasions
• First-degree burns
• Infected dermatoses (e.g., impetigo, folliculitis)
• Prophylaxis of bacterial infection in minor wounds and post-procedural skin disruptions
• Post-surgical wound care to prevent localized bacterial colonization

Clinically Accepted Off-Label Uses:

• Ophthalmic infections (e.g., blepharitis, bacterial conjunctivitis) when prepared in ophthalmic formulations
• External otitis (otitis externa) in specially formulated otic drops
• Post-laser dermatologic procedures and minor dermatologic surgeries for infection prevention
• Peristomal skin care in ostomy patients to reduce localized infection risk

Route of Administration:

• Topical (cutaneous)
• Ophthalmic and otic use when specifically formulated

Topical Dosage (Adults and Children ≥2 years):

• Clean the affected area before application
• Apply a thin layer 1 to 3 times daily
• May be covered with a sterile bandage if necessary

Ophthalmic Use (Formulated Eye Drops/Ointment Only):

• Apply as directed, usually 1–2 drops or 1 cm ointment strip every 3–4 hours

Otic Use (Formulated Drops Only):

• Instill 2–4 drops into the affected ear 3–4 times daily

Pediatrics (<2 years):

• Use only under medical supervision
• Avoid large surface areas or occlusive dressings due to systemic absorption risk

Elderly:

• No specific dose adjustment required

Renal or Hepatic Impairment:

• Use with caution in renal impairment if applied over large areas or damaged skin, due to possible systemic absorption of Polymyxin B
• No hepatic adjustment required

Duration of Treatment:

• Use for no more than 7 consecutive days, unless advised by a physician

Bacitracin Zinc + Polymyxin B Sulfate is a topical combination of two bactericidal antibiotics that act through complementary mechanisms.
Bacitracin Zinc inhibits bacterial cell wall synthesis by blocking the dephosphorylation of the lipid carrier required for peptidoglycan transport, primarily effective against gram-positive organisms such as Staphylococcus aureus and Streptococcus pyogenes.
Polymyxin B Sulfate binds to lipopolysaccharides on the outer membrane of gram-negative bacteria, disrupting membrane integrity, increasing permeability, and leading to leakage of intracellular contents and bacterial death.
Together, they offer broad-spectrum antibacterial activity for localized infections.

• Absorption: Negligible systemic absorption through intact skin; increased absorption through broken skin, mucous membranes, or prolonged use
• Distribution: Localized at the site of application; does not distribute systemically unless absorbed
• Metabolism: Not significantly metabolized
• Excretion: If absorbed, Polymyxin B is primarily excreted renally; Bacitracin is also renally excreted
• Onset of Action: Begins within 1–2 hours after topical application
• Half-life: Not applicable for topical use due to minimal systemic exposure
• Bioavailability: Minimal with topical use; significant only with mucosal or extensive exposure

Pregnancy:

• FDA Category C (for both components)
• Use only if clearly needed, especially on large areas, broken skin, or under occlusive dressings
• Systemic absorption is unlikely when applied to intact skin

Lactation:

• Safe when applied to small, intact areas and away from the breast/nipple area
• Avoid application to areas that could come into direct contact with the infant’s mouth
• No known excretion into breast milk; low risk of infant exposure

• Primary Class: Topical Antibiotic
• Subclasses:
• Bacitracin: Polypeptide antibiotic (effective mainly against gram-positive bacteria)
• Polymyxin B: Cyclic lipopeptide antibiotic (active against gram-negative organisms)

• Known hypersensitivity to Bacitracin, Polymyxin B, or any component of the preparation
• Use on large open wounds, severe burns, or deep puncture wounds
• Ophthalmic or otic use of non-sterile topical formulations
• Use in neonates or premature infants unless specifically directed

• Avoid prolonged use to prevent emergence of resistant organisms or fungal overgrowth
• Systemic absorption may occur when used on large or damaged skin areas, especially in renal impairment
• May cause nephrotoxicity or neurotoxicity if absorbed in significant amounts
• Use caution in pregnant women, young children, and patients with impaired renal function
• Discontinue use if signs of local irritation, sensitization, or allergic reaction appear
• Do not ingest or use near eyes unless ophthalmic formulation is used

Common (Localized, Mild):

• Itching
• Redness
• Mild burning or stinging
• Dryness or peeling at the application site

Less Common:

• Contact dermatitis
• Urticaria (hives)
• Swelling or rash

Serious or Rare:

• Anaphylaxis
• Nephrotoxicity (with large-area use and systemic absorption)
• Neurotoxicity (e.g., paresthesia, dizziness)

Onset & Severity:

• Local effects usually occur within the first few days
• Systemic effects are rare but serious when they occur, typically only after significant absorption

• Aminoglycosides (e.g., gentamicin): Additive nephrotoxicity if absorbed systemically
• Neuromuscular blockers: Risk of enhanced neuromuscular blockade if Polymyxin B is absorbed
• Other topical antibiotics: May increase risk of skin irritation or allergic reactions

Enzyme Systems:

• No interactions with CYP450 isoenzymes
• Systemic pharmacokinetic interactions are not relevant with proper topical use

• Regulatory guidance highlights the importance of limiting use to ≤7 days without reassessment
• Clinical preference is shifting toward narrow-spectrum alternatives (e.g., Mupirocin) in areas with rising resistance
• Combination topical antibiotic formulations like Bacitracin + Polymyxin B are still widely used for minor wound care but should be used judiciously to minimize resistance and sensitization

• Temperature: Store at 20°C to 25°C (may tolerate 15°C to 30°C excursions)
• Humidity: Store in a dry place with the cap tightly closed
• Light Protection: Keep away from direct sunlight
• Freezing: Do not freeze
• Handling Instructions:
• For external use only
• Do not share tubes or containers between individuals
• Discard if discolored or expired
• For ophthalmic/otic formulations, use only as prescribed and discard after 28 days of opening