Dexagen G

Approved Indications:

• Treatment of ocular inflammatory conditions associated with bacterial infections or risk of infection, including:
• Bacterial conjunctivitis
• Blepharitis
• Keratitis
• Uveitis with associated bacterial infection
• Postoperative ocular inflammation and infection prophylaxis (e.g., after cataract surgery)

Off-label/Clinically Accepted Uses:

• Treatment of other superficial ocular infections with inflammation caused or complicated by susceptible bacteria.
• Adjunct therapy in corneal abrasions at risk of bacterial superinfection.

Adults and Pediatrics (>1 year):

• Ophthalmic Suspension or Drops:
  Instill 1–2 drops in the affected eye(s) every 2 hours while awake for the first 2 days.
  Then, reduce to 1 drop every 4 to 6 hours for an additional 5 to 7 days or as directed by the physician.

Special Populations:

• Elderly: No specific dose adjustment; monitor for steroid-related adverse effects.
• Renal or Hepatic Impairment: No dose adjustment required for topical administration.
• Contact Lens Wearers: Remove lenses before use; wait at least 15 minutes before reinsertion.

Administration Instructions:

• Shake well before use to ensure uniform suspension.
• Avoid contamination by not touching dropper tip to any surface.
• Complete full course of therapy to prevent relapse.

Gatifloxacin is a fluoroquinolone antibiotic that inhibits bacterial DNA gyrase and topoisomerase IV, enzymes critical for bacterial DNA replication, transcription, and repair. This inhibition leads to bacterial cell death by preventing DNA synthesis.

Dexamethasone is a potent corticosteroid that reduces inflammation by inhibiting multiple inflammatory cytokines and mediators. It decreases capillary permeability, leukocyte migration, and suppresses immune response, thus controlling ocular inflammation, redness, and swelling.

The combination provides both antimicrobial action against susceptible bacteria and anti-inflammatory effects to alleviate ocular inflammation, improving therapeutic outcomes in infectious ocular diseases.

• Absorption: Topical ocular administration results in minimal systemic absorption; ocular tissue penetration is adequate for local therapeutic effect.
• Distribution: Gatifloxacin and dexamethasone penetrate ocular tissues including cornea, conjunctiva, and aqueous humor.
• Metabolism: Systemic metabolism negligible due to minimal absorption; dexamethasone is metabolized hepatically if absorbed systemically.
• Elimination: Primarily via tear drainage and minimal systemic clearance.
• Half-life: Ocular half-life varies; systemic half-life of dexamethasone approximately 3.5 hours if absorbed.

• Pregnancy:
• Gatifloxacin: FDA Category C (animal studies show risk; no adequate human studies).
• Dexamethasone: FDA Category C.
  Use only if potential benefits justify potential fetal risk.
• Lactation:
  Minimal systemic absorption suggests low risk; however, caution advised. Consult healthcare provider before use during breastfeeding.

• Primary Class:
• Gatifloxacin: Fluoroquinolone antibiotic
• Dexamethasone: Corticosteroid anti-inflammatory
• Combined Formulation: Antibacterial + Anti-inflammatory ophthalmic agent

• Known hypersensitivity to gatifloxacin, dexamethasone, or any formulation components.
• Viral, fungal, or mycobacterial ocular infections (risk of worsening infection).
• Herpes simplex keratitis and other corneal viral infections.
• Use in patients with untreated ocular tuberculosis.
• Glaucoma patients (use with caution due to steroid effects on intraocular pressure).

• Steroid-Related Risks:
• Potential for increased intraocular pressure, glaucoma, and cataract formation with prolonged use.
• Delay in healing of corneal ulcers.
• Infection Risk: Corticosteroids can mask symptoms and exacerbate infections; use only when bacterial infection is present or strongly suspected.
• Hypersensitivity: Risk of allergic reactions; discontinue if signs of hypersensitivity develop.
• Monitor:
• Intraocular pressure during prolonged therapy.
• Signs of secondary infection or worsening symptoms.
• Pediatric Use: Safety and efficacy established for children over 1 year; avoid in younger infants unless directed.

Common Adverse Effects:

• Ocular burning, stinging, irritation
• Blurred vision
• Eyelid edema
• Eye dryness or tearing

Serious and Rare Side Effects:

• Elevated intraocular pressure/glaucoma
• Posterior subcapsular cataract (with long-term use)
• Secondary ocular infections
• Hypersensitivity reactions (rash, itching, swelling)
• Delayed corneal healing or corneal thinning

Onset: Most side effects appear within days of treatment initiation; steroid-related effects usually develop with prolonged therapy.

• No significant drug-drug interactions expected due to minimal systemic absorption.
• Concurrent use of other ophthalmic drugs requires timing separation to avoid washout.
• Systemic CYP3A4 inducers or inhibitors do not affect topical dexamethasone significantly.
• Avoid concurrent use with other topical steroids without medical supervision.

• Regulatory guidance stresses cautious use of topical corticosteroids due to risk of intraocular pressure elevation.
• Combination products recommended primarily for infections with significant inflammation.
• Recent guidelines emphasize limited duration therapy and regular monitoring of intraocular pressure.
• Antibiotic stewardship encourages use only when bacterial infection is confirmed or strongly suspected to reduce resistance.

• Store at controlled room temperature 20°C to 25°C (68°F to 77°F).
• Protect from light and excessive heat.
• Keep container tightly closed.
• Do not freeze.
• Shake well before each use.
• Discard 28 days after opening or as per manufacturer’s instructions.