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Riboflavin 5'-Phosphate

Medically reviewed on Nov 20, 2018


(RYE boe flay vin five FOS fate)

Index Terms

  • Photrexa
  • Photrexa Viscous

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution Prefilled Syringe, Ophthalmic:

Photrexa Viscous: 0.146% in Dextran 20% (3 mL)

Photrexa-Photrexa Viscous Kit: Photrexa 0.146%; Photrexa Viscous 0.146% in Dextran 20% (6 mL) [contains dextran]

Brand Names: U.S.

  • Photrexa Viscous
  • Photrexa-Photrexa Viscous Kit

Pharmacologic Category

  • Corneal Collagen Cross-Linking Agent, Ophthalmic
  • Ophthalmic Agent


Photo enhancer that generates singlet oxygen in corneal collagen cross-linking.

Use: Labeled Indications

Corneal ectasia following refractive surgery: Treatment of corneal ectasia following refractive surgery with the KXL System in corneal collagen cross-linking.

Keratoconus, progressive: Treatment of progressive keratoconus with the KXL System in corneal collagen cross-linking.


There are no contraindications listed in the manufacturer's labeling.

Dosing: Adult

Corneal ectasia following refractive surgery; Keratoconus, progressive: Ophthalmic: Instill 1 drop every 2 minutes for 30 minutes following debridement of the epithelium to a diameter of ~9 mm. After 30 minutes, examine the eye under the slit lamp for the presence of a yellow flare in the anterior chamber. If flare is not detected, instill 1 drop every 2 minutes for an additional 2 to 3 drops and recheck for flare. Repeat as necessary. Once the flare is observed, perform ultrasound pachymetry. If corneal thickness is <400 microns, instill 2 drops every 5 to 10 seconds until the corneal thickness increases to ≥400 microns. Once the 400 micron threshold is met, irradiate the eye for 30 continuous minutes using the KXL System. During irradiation, instill riboflavin 5’-phosphate onto the eye every 2 minutes for the 30 minute irradiation period.

Dosing: Pediatric

Corneal ectasia following refractive surgery; Keratoconus, progressive: Ophthalmic: Adolescents ≥14 years: Refer to adult dosing.

Dosing: Renal Impairment

There are no dosage adjustments provided in the manufacturer’s labeling

Dosing: Hepatic Impairment

There are no dosage adjustments provided in the manufacturer’s labeling


For topical ophthalmic use; do not inject. For use with the KXL System only.


Store at 15°C to 25°C (59°F to 77°F); protect from light once removed from packaging.

Drug Interactions

There are no known significant interactions.

Adverse Reactions


Central nervous system: Foreign body sensation of eye (14% to 15%)

Ophthalmic: Corneal opacity (haze) (64% to 71%), corneal disease (3% to 28%), eye pain (17% to 26%), punctate keratitis (20% to 25%), corneal edema (in progressive keratoconus patients: 24%; all other patients: 3% to 9%), photophobia (2% to 19%), blurred vision (16% to 17%), ocular hyperemia (8% to 14%), dry eye syndrome (6% to 14%), decreased visual acuity (10% to 11%)

1% to 10%:

Central nervous system: Headache (4% to 8%)

Ophthalmic: Increased lacrimation (5% to 10%), eye discomfort (9%), conjunctival edema (7%), eyelid edema (5% to 6%), anterior chamber inflammation (2% to 6%), visual impairment (3% to 4%), blepharitis (3%), keratitis (1% to 3%), asthenopia (2%), diplopia (2%), eye discharge (2%), eye pruritus (2%), vitreous detachment (2%), eye injury (associated with device; 1% to 2%), visual halos around lights (1% to 2%)


Concerns related to adverse effects:

• Ulcerative keratitis: May occur; monitor for resolution of epithelial defects.

Monitoring Parameters

Resolution of epithelial defects

Pregnancy Considerations

Animal reproduction studies have not been conducted with riboflavin 5'-phosphate. The manufacturer recommends that the corneal collagen cross-linking procedure not be done during pregnancy. Pregnancy may be a risk factor for the progression of keratoconus (Bilgihan 2011).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience blurred vision, seeing floaters, dry eyes, foreign body sensation, tearing, headache, or sensitivity to light. Have patient report immediately to prescriber vision changes, severe eye pain, or severe eye irritation (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.