Cysteamine ophthalmic
Dry eye · Rx
Trade namesCystaran 0.44%, Cystadrops 0.37% (viscous)
Drug classCystine-depleting agent (orphan)
Strength0.44% (Cystaran), 0.37% (Cystadrops)
AvailabilityRx
Mechanism of actionReacts with intralysosomal cystine to form cysteine and a cysteine-cysteamine mixed disulfide that can exit the lysosome, dissolving the corneal cystine crystals of cystinosis.
Indication / reason for useCorneal cystine crystal accumulation in cystinosis.
Usual adult dosingCystaran: 1 drop in each eye every waking hour (≈q1h). Cystadrops: 1 drop 4×/day (viscous, less frequent).
PreservativeBAK (Cystadrops); Cystaran is preservative-free , a preservative-free option exists
Contact lensesRemove lenses; reinsert after 15 minutes.
Common / important adverse effectsSensitivity to light, redness, eye pain, blurred vision, deposits on the lashes/lids; Cystaran's hourly schedule is demanding.
Contraindications & cautionsHypersensitivity.
Pregnancy / lactationLimited data.
Practice notesAdherence is the main challenge with the hourly formulation; Cystadrops' 4×/day viscous dosing improves it. Keep refrigerated.
Chair-side reference only. Dosing, contraindications and pregnancy guidance here are not exhaustive. Confirm against the current prescribing information and the patient’s full history before prescribing or advising.