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Prescribing Information


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How Does CYSTARAN Work?

Cysteamine acts as a cystine-depleting agent. It enters the cystinotic lysosome and reacts with the cystine. The result is cysteine and cysteine-cysteamine mixed disulfides. These molecules are able to exit the lysosome via a transport system. This ultimately results in reduction of the corneal cystine crystals.1-3

CYSTARAN reduces corneal cystine crystals

Cystine crystals within the cornea viewed with slit-lamp photography4


This patient was aged 5 years 9 months at the start of treatment.

Please see the CYSTARAN Prescribing Information for more information.


References: 1. CYSTARAN [prescribing information]. Gaithersburg, MD: Leadiant Biosciences, Inc.; 2020. 2. Cystinosis Research Network Web site. Cystinosis symptoms & treatment. Available at: Accessed March 13, 2013. 3. Elenberg E. eMedicine Pediatrics: General Medicine Web site. Cystinosis. Available at: Accessed March 13, 2013. 4. Gahl WA, Kuehl EM, Iwata F, Lindblad A, Kaiser-Kupfer MI. Corneal crystals in nephropathic cystinosis: natural history and treatment with cysteamine eyedrops. Mol Genet Metab. 2000;71:100-120.



CYSTARAN (CYSTEAMINE OPHTHALMIC SOLUTION) 0.44% STERILE is a cystine-depleting agent indicated for the treatment of corneal cystine crystal accumulation in patients with cystinosis.

Important Safety Information:

To minimize contaminating the dropper tip and solution, care should be taken not to touch the eyelids or surrounding areas with the dropper tip of the bottle. Keep bottle tightly closed when not in use.

There have been reports of benign intracranial hypertension (or pseudotumor cerebri) associated with oral cysteamine treatment that has resolved with the addition of diuretic therapy. There have also been reports associated with ophthalmic use of cysteamine; however, all of these patients were on concurrent oral cysteamine.

CYSTARAN contains benzalkonium chloride, which may be absorbed by soft contact lenses. Contact lenses should be removed prior to application of solution and may be reinserted 15 minutes following its administration.

CYSTARAN is for topical ophthalmic use only.

The most frequently reported ocular adverse reactions occurring in ≥ 10% of patients were sensitivity to light, redness, and eye pain/irritation, headache and visual field defects.