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Gentamicin (Ophthalmic)

Medically reviewed by Last updated on Sep 13, 2019.


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Index Terms

  • Gentamicin Sulfate

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Ointment, Ophthalmic:

Gentak: 0.3% (3.5 g) [contains methylparaben, propylparaben]

Generic: 0.3% (3.5 g [DSC])

Solution, Ophthalmic:

Generic: 0.3% (5 mL, 15 mL [DSC])

Brand Names: U.S.

  • Gentak

Pharmacologic Category

  • Antibiotic, Aminoglycoside
  • Antibiotic, Ophthalmic


Interferes with bacterial protein synthesis by binding to 30S ribosomal subunit resulting in a defective bacterial cell membrane


Ophthalmic drops: Systemic absorption: Undetected (<0.5 mcg/mL)

Use: Labeled Indications

Ophthalmic infections: Topical treatment of ocular bacterial infections, including conjunctivitis, keratitis, keratoconjunctivitis, corneal ulcers, blepharitis, blepharoconjunctivitis, acute meibomianitis, and dacryocystitis caused by Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Streptococcus pneumoniae, Enterobacter aerogenes, Escherichia coli, Haemophilus influenza, Klebsiella pneumonia, Neisseria gonorrhoeae, Pseudomonas aeruginosa, and Serratia marcescens.


Hypersensitivity to gentamicin or any component of the formulation

Dosing: Adult

Ophthalmic infections: Ophthalmic:

Ointment: Instill 1/2" (1.25 cm) 2 to 3 times daily

Solution: Instill 1 to 2 drops every 4 hours, up to 2 drops every hour for severe infections

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Ophthalmic infections: Ophthalmic:

Ointment: Instill 1/2 inch (1.25 cm) to affected eye(s) 2 to 3 times/day

Solution: Instill 1 to 2 drops into affected eye(s) every 4 hours; up to 2 drops every hour for severe infections


For topical ophthalmic use only; not for injection into the eye. Avoid contaminating tip of the solution container or ointment tube.


Store at controlled room temperature of 20°C to 25°C (68°F to 77°F).

Drug Interactions

There are no known significant interactions.

Adverse Reactions

>1%: Ophthalmic: Burning sensation of eyes, eye irritation

<1%, postmarketing, and/or case reports: Corneal ulcer, hallucination, hypersensitivity reaction, purpura, thrombocytopenia


Concerns related to adverse effects:

• Corneal healing: May delay corneal healing.

• Sensitization: Topical use has been associated with local sensitization (redness, irritation); discontinue if sensitization is noted.

• Superinfection: Prolonged use may result in fungal or bacterial superinfection; if purulent discharge, inflammation, or pain are increased, therapy should be re-evaluated.

Other warnings/precautions:

• Appropriate use: Not for injection into the eye.

• Long-term use: Not intended for long-term therapy.

Pregnancy Risk Factor


Pregnancy Considerations

Adverse events were observed following systemic administration of gentamicin in animal reproduction studies. The amount of gentamicin available systemically following application of the ophthalmic drops is below the limit of detection (<0.5 mcg/mL) (Trope 1979). In general, if ophthalmic agents are needed in pregnant women, the minimum effective dose should be used in combination with punctal occlusion to decrease systemic absorption (Samples 1988).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience burning. Have patient report immediately to prescriber vision changes, eye pain, or severe eye irritation (HCAHPS)

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.