Neomycin Sulphate + Polymyxin B Sulphate + Pramoxine

Approved Indications:

• Minor Superficial Skin Infections with Pain or Itching
  Indicated for the prevention and treatment of superficial bacterial infections resulting from minor cuts, scrapes, abrasions, insect bites, and minor burns, where pain, itching, or irritation is present.
• Localized Infected Dermatoses
  Used for treating superficial skin infections associated with impetigo, infected dermatitis, or eczema that present with localized discomfort or itching.
• Post-procedural Wound Care
  Applied after minor dermatologic procedures (e.g., mole removal, suturing, skin biopsy) to prevent infection and provide symptomatic relief.

Clinically Accepted Off-Label Uses:

• Symptomatic Relief in Infected Perianal Lesions
  Occasionally used for symptomatic relief of external hemorrhoids or perianal irritation due to its anesthetic component, although not officially approved for this indication.

Adults:

• Apply a thin layer to the affected area 1 to 3 times daily.
• A sterile dressing may be applied if needed.
• Avoid application to large surface areas or for prolonged periods.

Pediatrics (≥2 years):

• Apply 1 to 2 times daily under adult supervision.
• Avoid use in children under 2 years of age unless directed by a physician.

Elderly:

• Same as adult dosage.
• Monitor for skin sensitivity reactions with extended use.

Renal Impairment:

• Use with caution, especially if applying to broken skin, due to potential systemic absorption of neomycin and polymyxin B, which may cause nephrotoxicity.

Hepatic Impairment:

• No dosage adjustment is necessary, but prolonged or extensive application should be avoided.

Route of Administration:

• Topical (cutaneous) use only.
• Not for ophthalmic, otic (with ruptured eardrum), intranasal, or mucosal use.

Treatment Duration:

• Typically used for up to 7 consecutive days.
• Prolonged use is not recommended unless prescribed by a healthcare professional.

This combination medication works through complementary antibacterial and anesthetic mechanisms:

• Neomycin Sulfate is an aminoglycoside antibiotic that binds irreversibly to the 30S subunit of bacterial ribosomes, inhibiting protein synthesis and leading to bacterial cell death. It is effective primarily against Gram-negative organisms.
• Polymyxin B Sulfate acts on the bacterial cell membrane of Gram-negative bacteria by disrupting membrane phospholipids, leading to increased permeability, leakage of intracellular contents, and bacterial death.
• Pramoxine Hydrochloride is a local anesthetic that inhibits voltage-gated sodium channels on neuronal membranes, preventing the initiation and transmission of nerve impulses. This provides rapid relief from pain and itching at the site of application.

Together, these agents provide broad-spectrum antibacterial action along with localized anesthetic relief.

• Absorption:
  Minimal systemic absorption through intact skin. Absorption increases significantly when applied to broken skin or large areas.
• Distribution:
  If absorbed, neomycin and polymyxin B are distributed in extracellular fluids. Pramoxine remains largely localized at the application site.
• Metabolism:
  Neomycin and polymyxin B are not metabolized extensively. Pramoxine undergoes hepatic metabolism if absorbed systemically.
• Excretion:
  Systemically absorbed neomycin and polymyxin B are excreted unchanged in the urine. Pramoxine metabolites are also eliminated renally.
• Half-life:
  Neomycin: approximately 2–3 hours (if systemically absorbed).
  Pramoxine: Not well-defined due to limited systemic absorption.

Pregnancy:

• FDA Pregnancy Category C
  Animal studies have shown adverse effects on the fetus; adequate studies in pregnant women are lacking. Use only if the potential benefit justifies the potential risk to the fetus.

Lactation:

• Topical use is not expected to result in significant systemic exposure.
  Avoid applying to the breast area to prevent infant ingestion.
  Use with caution during breastfeeding.

• Topical Antibacterial and Anesthetic Combination
• Neomycin Sulfate: Aminoglycoside antibiotic
• Polymyxin B Sulfate: Cyclic polypeptide antibiotic
• Pramoxine Hydrochloride: Topical local anesthetic (non-ester, non-amide class)

• Known hypersensitivity to neomycin, polymyxin B, pramoxine, or any other component of the formulation
• Perforated tympanic membrane
• Extensive open wounds or large surface area burns
• History of neomycin-induced ototoxicity or nephrotoxicity
• Use in infants under 2 years without medical advice

• Systemic Toxicity:
  Prolonged use or application to broken skin may lead to systemic absorption of neomycin and polymyxin B, increasing the risk of nephrotoxicity and ototoxicity.
• Allergic Reactions:
  Neomycin is a common sensitizer and may cause allergic contact dermatitis. Discontinue use if redness, rash, or swelling occurs.
• Superinfection Risk:
  Prolonged use may promote overgrowth of non-susceptible organisms, including fungi.
• Pramoxine Sensitivity:
  Though rare, allergic or irritant reactions may occur. Avoid contact with eyes, mucous membranes, or deep wounds.
• Avoid Use in Otic, Nasal, or Ocular Areas:
  Not intended for use in or around the eyes, nose, or ears (unless tympanic membrane is intact and use is specifically prescribed).

Common (Dermatologic):

• Local burning, stinging, or itching at the application site
• Mild redness or irritation
• Temporary numbness

Less Common:

• Allergic contact dermatitis (neomycin-associated)
• Localized hypersensitivity reactions

Serious (Rare):

• Ototoxicity (hearing loss, especially if absorbed systemically)
• Nephrotoxicity (with extensive use or application to damaged skin)
• Anaphylaxis (extremely rare)

Timing and Severity:

• Most adverse effects are mild and appear within the first few days of use.
• Serious reactions are rare and usually linked to prolonged, high-dose, or inappropriate use.

• Systemic Aminoglycosides or Polymyxins:
  Increased risk of cumulative ototoxicity and nephrotoxicity when combined with systemic aminoglycosides.
• Loop Diuretics (e.g., furosemide):
  May increase the ototoxic risk of neomycin when systemically absorbed.
• Neuromuscular Blockers:
  Potential enhancement of neuromuscular blockade by systemically absorbed neomycin.
• CYP450 Enzyme Interactions:
  Minimal involvement; pramoxine metabolism does not significantly affect CYP450 enzymes.

• Safety Alerts:
  Medical guidelines emphasize limited duration of use (no longer than 7 days) due to increasing reports of neomycin-induced dermatitis.
• Label Updates:
  Packaging now includes clearer warnings about not using on large or broken skin areas and the risks of systemic toxicity.
• Bangladesh Brand Verification (Medex.com.bd):
  Commonly marketed under brands such as Polynema Plus®, Neomex Plus®, Neoprox®, available as cream or ointment.

• Temperature: Store between 20°C to 25°C (68°F to 77°F).
  Allowable excursions between 15°C and 30°C.
• Humidity and Light Protection:
  Keep in a dry place, protected from direct light and excess moisture.
• Handling Instructions:
• Keep the cap tightly closed after each use
• Do not freeze
• Discard after expiry or if formulation appears discolored
• For external use only
• Refrigeration: Not required.