Which antibiotic is recommended for corneal foreign body in a patient who does not wear contact lenses?

Which antibiotic is recommended for corneal foreign body in a patient who does not wear contact lenses?

• A. Erythromycin
• B. Ciprofloxacin
• C. Ofloxacin
• D. Tobramycin

Answer: (A)

The key idea is that antibiotic choice after a corneal foreign body depends on contact lens usage, which shifts the risk toward Pseudomonas. In someone who does not wear contact lenses, coverage of the typical Gram-positive ocular flora is usually sufficient. Erythromycin ointment provides solid protection against common Gram-positive pathogens that can cause infection after corneal abrasions or foreign bodies, and its ointment form helps the drug stay on the ocular surface longer for effective prophylaxis. In contrast, fluoroquinolones like ciprofloxacin or ofloxacin, and aminoglycosides like tobramycin, offer broader coverage including Pseudomonas and are more commonly reserved for contact lens wearers or more severe/infected ulcers. Thus erythromycin is the best initial choice in this setting.

The key idea is that antibiotic choice after a corneal foreign body depends on contact lens usage, which shifts the risk toward Pseudomonas. In someone who does not wear contact lenses, coverage of the typical Gram-positive ocular flora is usually sufficient. Erythromycin ointment provides solid protection against common Gram-positive pathogens that can cause infection after corneal abrasions or foreign bodies, and its ointment form helps the drug stay on the ocular surface longer for effective prophylaxis. In contrast, fluoroquinolones like ciprofloxacin or ofloxacin, and aminoglycosides like tobramycin, offer broader coverage including Pseudomonas and are more commonly reserved for contact lens wearers or more severe/infected ulcers. Thus erythromycin is the best initial choice in this setting.