Polymix G(25 IU+1700 IU+5000 IU)/ml

Polymix G is a fixed-dose topical antibiotic combination used for the prevention and treatment of superficial bacterial infections caused by susceptible organisms. Its use is classified by strength of evidence below:

Established / Approved Uses

• Superficial bacterial infections of the eye and its adnexa, including bacterial conjunctivitis, blepharitis, and blepharoconjunctivitis, caused by susceptible gram-positive and gram-negative organisms.
• Superficial bacterial infections of the external ear canal (otitis externa) due to susceptible bacteria, where the tympanic membrane is intact.

Adjunct / Prophylactic Use

• Prophylaxis against bacterial infection following minor corneal abrasion or foreign body removal, and after certain minor ophthalmic procedures, as advised by an eye specialist.

Polymix G is not effective against viral, fungal, or mycobacterial infections and should not be used for these conditions.

Each mL (or equivalent unit dose) of Gramacidin + Neomycin + Polymixin B contains three complementary antibacterial agents:

• Gramicidin — a cyclic polypeptide antibiotic active mainly against gram-positive bacteria.
• Neomycin (as neomycin sulfate) — an aminoglycoside antibiotic with broad activity against many gram-negative and some gram-positive bacteria.
• Polymyxin B (as polymyxin B sulfate) — a polypeptide antibiotic with potent activity against gram-negative bacteria, including Pseudomonas aeruginosa.

Polymix G is a multi-component topical anti-infective preparation combining three antibiotics that act through different mechanisms to provide broad-spectrum coverage against common gram-positive and gram-negative bacteria responsible for superficial eye and ear infections. It is typically formulated as a sterile ophthalmic/otic solution or suspension for local application and is not intended for systemic (oral or injectable) use.

Polymix G belongs to the therapeutic class of topical (ophthalmic/otic) anti-infective combinations, specifically a multi-antibiotic combination of a polypeptide antibiotic (gramicidin), an aminoglycoside (neomycin), and a polypeptide antibiotic (polymyxin B).

Gramacidin + Neomycin + Polymixin B combines three antibacterial agents with complementary and synergistic mechanisms of action:

• Gramicidin forms channels in bacterial cell membranes that disrupt ion transport and membrane permeability, leading to cell death in susceptible gram-positive organisms.
• Neomycin binds irreversibly to the bacterial 30S ribosomal subunit, causing misreading of mRNA and inhibition of protein synthesis, resulting in a bactericidal effect against many gram-negative and some gram-positive bacteria.
• Polymyxin B binds to the lipopolysaccharide and phospholipid components of the outer cell membrane of gram-negative bacteria, increasing membrane permeability and causing leakage of intracellular contents and cell death.

Together, this combination provides broad-spectrum bactericidal coverage against most common pathogens implicated in superficial ocular and otic infections, including staphylococci, streptococci, Haemophilus influenzae, Escherichia coli, and Pseudomonas aeruginosa.

For topical use only (ophthalmic or otic route as prescribed). Tilt the head back (for eye use) or to the side (for ear use), instill the prescribed number of drops, and avoid contaminating the dropper tip. Keep eyes closed gently for 1–2 minutes after instilling eye drops. Do not use Polymix G orally or by injection.

Clinically significant interactions with Polymix G are uncommon due to minimal systemic absorption when used topically as directed; however, the following should be noted:

• Other ototoxic or nephrotoxic drugs (e.g., systemic aminoglycosides, loop diuretics): concurrent or prior use, especially with prolonged or extensive topical application on broken skin/large areas, may theoretically add to ototoxic/nephrotoxic risk from absorbed neomycin/polymyxin B.
• Other topical eye or ear preparations: if multiple topical products are prescribed, separate administration by at least 5–10 minutes to prevent dilution or washout of each product.

Most side effects of Polymix G are local and mild, but should be reported if persistent or severe:

• Transient burning, stinging, or itching at the site of application.
• Local hypersensitivity or allergic contact dermatitis (notably associated with neomycin).
• Redness, swelling, or irritation of the treated eye or ear.
• Rarely, superinfection with non-susceptible organisms (including fungi) with prolonged use.
• Systemic absorption is minimal with normal topical use, so systemic effects such as ototoxicity or nephrotoxicity are rare but see Precautions and Warnings for conditions that increase this risk.

Data on the use of Polymix G during pregnancy and lactation are limited. Although systemic absorption from topical ophthalmic or otic use is generally minimal, this medicine should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus. Caution is advised during breastfeeding as well; consult a physician before use in pregnant or breastfeeding women.

• Avoid prolonged or widespread use of Polymix G, particularly on large denuded or abraded areas, as increased systemic absorption of neomycin and polymyxin B may carry a risk of ototoxicity and nephrotoxicity.
• Neomycin is a relatively common cause of contact sensitization; discontinue if signs of hypersensitivity (increasing redness, itching, swelling) develop.
• Extended use may result in overgrowth of non-susceptible organisms, including fungi; reassess if no improvement occurs within a few days.
• Do not use for viral, fungal, or mycobacterial infections (see Contraindications).
• Antibiotic stewardship: take exactly as prescribed by your physician; do not stop, extend, skip doses, or share this medicine with others without medical advice.

Topical overdose of Polymix G is unlikely to cause significant systemic toxicity, though excessive or prolonged application may increase local irritation or the theoretical risk of ototoxicity/nephrotoxicity. If accidental ingestion or significant overexposure occurs, or if severe irritation develops, seek immediate medical attention or contact a poison control center rather than attempting home treatment.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children. Do not freeze. Discard any remaining solution after the course of treatment or as directed on the label.

• Renal impairment: although systemic absorption from topical use is minimal, caution is advised in patients with significant renal impairment given the nephrotoxic potential of neomycin and polymyxin B with extensive use; see Precautions and Warnings.
• Hepatic impairment: no specific dose adjustment of Polymix G is established; use with routine caution.
• Elderly: no specific dose adjustment is generally required for topical use.
• Pediatric patients: see Pediatric Uses below.

Topical anti-infective combination: cyclic polypeptide antibiotic (gramicidin) + aminoglycoside antibiotic (neomycin) + polypeptide antibiotic (polymyxin B).

Gramacidin + Neomycin + Polymixin B acts through three complementary bactericidal mechanisms: gramicidin disrupts bacterial cell membrane permeability, neomycin inhibits bacterial protein synthesis via 30S ribosomal binding, and polymyxin B disrupts the outer membrane of gram-negative bacteria — together providing broad-spectrum coverage against susceptible gram-positive and gram-negative organisms.

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Polymix G may be used topically in children for approved ophthalmic and otic indications at the same drop-based dosing as adults, under medical supervision. Safety and efficacy in neonates and very young infants have not been well established, and use in this age group should be guided by a pediatrician. Prolonged or repeated use in children should be avoided due to the theoretical risk of systemic absorption and ototoxicity/nephrotoxicity, particularly with otic use.