Scanning electron microscopic study of a Ciloxan bottle blocked by ciprofloxacin crystals

To report blockage of a commercially available ciprofloxacin bottle by white crystalline deposits. This study evaluated the ultrastructural features of the ciprofloxacin crystals.

A patient underwent intensive topical treatment of an infectious corneal ulcer with commercially available ciprofloxacin 0.3% ophthalmic solution. During treatment, the patient was unable to obtain medication from the ciprofloxacin bottle and required a new prescription. Examination of the bottle revealed that about 50% of the medication remained, but compression of the bottle with any amount of force failed to deliver any medication. On closer examination, a white material partially filled the nozzle track of the bottle and was on the outer bottle near the nozzle and the inner surface of the bottle cap. These white crystalline deposits were evaluated by scanning electron microscopy.

Plate-like, needle, cable and spaghetti-like crystals were found. The needle crystals formed multiple petaloid patterns.

This is the first report of blockage of a commercially available ciprofloxacin 0.3% bottle by ciprofloxacin crystals and the inability to deliver medication from the bottle. Ultrastructural study of the white crystalline deposits revealed four types of ciprofloxacin crystals.