Which fluoroquinolone is most commonly used for Pseudomonas coverage in ocular infections?

• A. Levofloxacin
• B. Gatifloxacin
• C. Moxifloxacin
• D. Ciprofloxacin

Answer: (D)

When you need to cover Pseudomonas in an eye infection, potency against that organism is the deciding factor. Ciprofloxacin has the strongest anti-Pseudomonal activity among the commonly used ophthalmic fluoroquinolones, with reliably low MICs for Pseudomonas aeruginosa and good topical penetration to reach the cornea and tear film. That combination makes it the go-to choice when Pseudomonas is suspected or risk factors exist (like contact lens wear or corneal ulcers). The other fluoroquinolones—though they offer broad coverage and excellent activity against many Gram-negative and Gram-positive bacteria—don’t demonstrate the same consistent strength against Pseudomonas in ocular use, so they’re used with different emphasis or in different clinical scenarios.