What are the side effects of fluoroquinolone (Fluoroquinolone) eyedrops, such as moxifloxacin (Moxifloxacin) or ciprofloxacin (Ciprofloxacin)?

Fluoroquinolone Eyedrop Side Effects

Fluoroquinolone eyedrops are generally well-tolerated with minimal systemic toxicity, but can cause local ocular adverse events in 1-6% of patients, most commonly conjunctivitis, ocular discomfort, hyperemia, and dry eye. 1

Local Ocular Side Effects

The most frequently reported ocular adverse events include: 1

• Conjunctivitis, decreased visual acuity, dry eye, keratitis, ocular discomfort, ocular hyperemia (redness), ocular pain, ocular pruritus (itching), subconjunctival hemorrhage, and tearing - occurring in approximately 1-6% of patients 1
• Eye irritation and eye pain are among the most common treatment-related adverse events, with the majority being mild in severity 2
• Corneal precipitation can occur, particularly with ciprofloxacin and to a lesser extent norfloxacin, but does not appear to interfere with healing in most cases 3
  • However, corneal precipitation may delay healing and result in corneal perforation in approximately 10% of cases 4

Systemic Side Effects

Nonocular adverse events are uncommon but include: 1

• Fever, increased cough, infection, otitis media, pharyngitis, rash, and rhinitis - reported at rates of 1-4% 1
• Systemic toxicity is not a concern with topical ophthalmic fluoroquinolone therapy, as exposure is minimal compared to oral or intravenous administration 5

Serious Warnings and Precautions

Hypersensitivity Reactions

Although rare with topical use, serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported with systemically administered quinolones, some following the first dose. 1

• Reactions may include cardiovascular collapse, loss of consciousness, angioedema (laryngeal, pharyngeal, or facial edema), airway obstruction, dyspnea, urticaria, and itching 1
• If an allergic reaction occurs, discontinue the drug immediately 1
• Serious acute hypersensitivity reactions may require immediate emergency treatment with oxygen and airway management 1

Growth of Resistant Organisms

• Prolonged use may result in overgrowth of non-susceptible organisms, including fungi 1
• If superinfection occurs, discontinue use and institute alternative therapy 1

Class-Related Toxicities (Dose-Dependent)

While these are primarily concerns with systemic fluoroquinolone use, awareness is important: 4

• Phototoxicity and neurotoxicity have been reported 4
• Toxic effects on ocular collagen may be associated with Achilles tendinopathy 4
• Ocular toxicity appears to be dose-dependent and results from both class-effects and specific fluoroquinolone structures 4

Safety in Special Populations

• Fluoroquinolone eyedrops are approved for use in children ≥1 year of age for bacterial conjunctivitis 5
• Both moxifloxacin and besifloxacin were well tolerated in 447 pediatric patients aged 1-17 years with bacterial conjunctivitis 5

Important Clinical Caveats

• Patients should be advised not to wear contact lenses if they have signs or symptoms of bacterial conjunctivitis 1
• When used in therapeutic topical dosages, corneal toxicity does not typically occur 3
• In vivo studies in healthy adults showed no significant functional or morphological corneal changes after 7 days of moxifloxacin or levofloxacin use three times daily 6
• Moxifloxacin is contraindicated in patients with a history of hypersensitivity to moxifloxacin, other quinolones, or any components in the medication 1