Usage
This ophthalmic solution combines a fluoroquinolone antibiotic (moxifloxacin), a corticosteroid (dexamethasone), and a lubricant (hydroxypropyl methylcellulose). It is primarily prescribed for:
- Treatment of bacterial eye infections (e.g., bacterial conjunctivitis).
- Prevention of inflammation and infection after ocular surgery (e.g., cataract, LASIK).
- Reduction of post-operative inflammation.
Pharmacological Classification:
- Moxifloxacin: Fluoroquinolone antibiotic
- Dexamethasone: Corticosteroid
- Hydroxypropyl methylcellulose: Lubricant, viscosity-increasing agent
Mechanism of Action:
Moxifloxacin inhibits bacterial DNA gyrase and topoisomerase IV, essential enzymes for bacterial DNA replication. Dexamethasone suppresses inflammation by inhibiting prostaglandins and other inflammatory mediators. Hydroxypropyl methylcellulose lubricates the eye, mimicking natural tears.
Alternate Names
- Moxifloxacin/Dexamethasone Sterile Ophthalmic Solution
- Moxifloxacin + Dexamethasone eye drops
- Various brand names (e.g., Moxigrev-D, Zoxicin D, Moxquin D, Moxifloxacin and Dexamethasone Eye Drops, SYNAMOX D, MOSI-D, MOXIFAX)
How It Works
Pharmacodynamics: Moxifloxacin exerts bactericidal effects. Dexamethasone reduces inflammation, redness, swelling, and pain. Hydroxypropyl methylcellulose increases the viscosity of the solution, prolonging corneal contact time.
Pharmacokinetics: Moxifloxacin and dexamethasone penetrate ocular tissues after topical administration. Some systemic absorption can occur. Elimination pathways are primarily renal and hepatic for both drugs. Hydroxypropyl methylcellulose is not absorbed systemically.
Mode of Action: Moxifloxacin interferes with bacterial DNA replication. Dexamethasone binds to glucocorticoid receptors, modulating gene expression and inhibiting inflammatory pathways.
Dosage
Standard Dosage
Adults:
- Bacterial Conjunctivitis: 1 drop in the affected eye(s) 4 times daily for 7 days.
- Post-Operative: 1 drop 4 times daily, starting 1 day before surgery and continuing for up to 15 days post-operatively.
Children:
- Not recommended for children below 1 year of age.
- Children above 1 year: Use with caution under strict medical supervision. Similar dosing to adults may be considered.
Special Cases:
- Elderly Patients: No specific dose adjustment is typically needed.
- Patients with Renal Impairment: Dose adjustment not usually necessary.
- Patients with Hepatic Dysfunction: Dose adjustment not usually necessary.
- Patients with Comorbid Conditions: Careful monitoring for systemic side effects is crucial, particularly in patients with diabetes or glaucoma/ocular hypertension.
Clinical Use Cases
Dosages for these settings typically align with the standard adult recommendations above.
- Intubation: Not applicable for ophthalmic solution
- Surgical Procedures (Ocular): As described in post-operative dosage
- Mechanical Ventilation: Not applicable for ophthalmic solution
- Intensive Care Unit (ICU) Use: Not applicable for ophthalmic solution
- Emergency Situations: Not applicable for ophthalmic solution
Dosage Adjustments
No specific dosage adjustments are generally recommended based on renal or hepatic function.
Side Effects
Common Side Effects
- Temporary stinging or burning sensation
- Blurred vision
- Eye irritation or redness
- Dry eyes
- Headache
- Watery eyes
- Swelling of the eyelids
- Discomfort at the application site
- Subconjunctival hemorrhage (bleeding under the conjunctiva)
Rare but Serious Side Effects
- Allergic reactions (anaphylaxis)
- Tendon rupture (with systemic use of fluoroquinolones)
- Peripheral neuropathy (with systemic use of fluoroquinolones)
- CNS effects (with systemic use of fluoroquinolones)
- Severe eye pain
- Corneal ulceration
- Glaucoma
- Cataracts (with prolonged use)
Long-Term Effects
- Cataracts
- Glaucoma
- Secondary ocular infections
Contraindications
- Hypersensitivity to any component of the medication
- Viral (e.g., herpes simplex, varicella) or fungal eye infections
- Ocular tuberculosis
- Untreated glaucoma
Drug Interactions
- Other corticosteroids (increased risk of ocular hypertension/glaucoma)
- NSAIDs (increased risk of corneal perforation)
- Antidiabetic medications (may affect blood glucose control)
- Other ophthalmic medications (administer at least 5 minutes apart)
Pregnancy and Breastfeeding
- Pregnancy: FDA Category C. Use only if potential benefit justifies the risk to the fetus.
- Breastfeeding: Moxifloxacin and dexamethasone are excreted in breast milk. Use with caution and monitor the infant for potential side effects.
Drug Profile Summary
- Mechanism of Action: Moxifloxacin inhibits bacterial DNA replication; Dexamethasone suppresses inflammation. Hydroxypropylmethylcellulose lubricates the ocular surface.
- Side Effects: Eye discomfort, blurred vision, irritation, headache. Rare: allergic reactions, tendon rupture (systemic), corneal perforation.
- Contraindications: Hypersensitivity, viral/fungal/mycobacterial eye infections, untreated glaucoma.
- Drug Interactions: Other corticosteroids, NSAIDs, antidiabetic medications.
- Pregnancy & Breastfeeding: Use with caution. Potential fetal risk (Category C). Excretion in breast milk.
- Dosage: Adults/Children >1 year: 1 drop 4 times daily (specific durations depending on indication).
- Monitoring Parameters: Intraocular pressure, visual acuity, signs of infection/inflammation.
Popular Combinations
This combination itself is a popular formulation.
Precautions
- Do not touch the tip of the bottle to the eye or any other surface to avoid contamination.
- If using other ophthalmic solutions, wait at least 5 minutes between administrations.
- Remove contact lenses before instillation and avoid wearing them during treatment.
- Wash hands before and after use.
- Monitor for signs of adverse reactions.
- Do not inject the solution.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Dexamethasone + Hydroxypropylmethylcellulose + Moxifloxacin?
A: Adults and children over 1 year: 1 drop in affected eye(s) 4 times daily. Duration: 7 days for bacterial conjunctivitis; up to 15 days for post-operative use.
Q2: Can I use this medication if I have a viral eye infection?
A: No, this medication is contraindicated in viral eye infections.
Q3: Are there any serious side effects I should be aware of?
A: Although rare, serious side effects can include allergic reactions, corneal perforation, increased intraocular pressure, and cataracts with prolonged use.
A: No, you should avoid wearing contact lenses during treatment.
Q5: What should I do if I experience blurred vision after using the drops?
A: Blurred vision can be a temporary side effect. Wait until your vision clears before driving or operating machinery.
Q6: Can pregnant or breastfeeding women use this medication?
A: Use with caution during pregnancy (Category C) and breastfeeding. Weigh the potential benefits against the risks.
Q7: How should I store this medication?
A: Store in a cool, dry place away from direct sunlight.
Q8: What should I do if I miss a dose?
A: Instill the missed dose as soon as you remember, then continue with your regular dosing schedule. Do not double the dose.
Q9: Can this medication be used in children?
A: Use with caution in children over 1 year under strict medical supervision. Not recommended for children below 1 year of age.
