Epioxa and Epioxa HD

Epioxa and Epioxa HD are prescription eye solutions containing riboflavin (a form of vitamin B2) used together during a procedure called corneal collagen cross-linking to treat keratoconus in adults and pediatric patients 13 years and older. These solutions work as photoenhancers, meaning they enhance the effects of UV-A light treatment on the cornea.

Epioxa is used together with specialized medical equipment:

• O2n System: Delivers controlled UV-A light
• Boost Goggles: Provides oxygen during treatment.

The procedure strengthens the cornea without removing the outer layer of cells (epithelium-on technique).

FDA approval: The active ingredient riboflavin was first approved in 2016 for corneal cross-linking procedures. Epioxa and Epioxa HD were approved for use with the O2n system and Boost Googles on October 17, 2025.

Keratoconus is a progressive eye condition where the cornea (the clear front surface of your eye) gradually thins and bulges outward into a cone shape. This causes blurred vision, sensitivity to light, and difficulty seeing clearly. Corneal cross-linking helps strengthen the cornea to slow or stop this progression.

Epioxa and Epioxa HD are FDA-approved for:

• Adults and adolescents 13 years and older with keratoconus
• Use during epithelium-on corneal collagen cross-linking procedures.

During the cross-linking procedure, riboflavin 5'-phosphate is applied to your cornea and activated by UV-A light. This creates chemical bonds (cross-links) between collagen fibers in the cornea, which:

• Strengthens corneal tissue
• Stiffens the cornea
• Helps stop or slow the progression of keratoconus
• Preserves vision.

The "epithelium-on" technique means the outer layer of your cornea stays intact during treatment, which may lead to faster healing compared to older methods.

Herpetic keratitis (eye herpes)

If you have a history of herpes simplex virus infection in your eye, tell your doctor. The procedure may reactivate the infection. Your doctor will carefully evaluate whether treatment is appropriate for you.

Absolute Contraindications

Do NOT use Epioxa if you:

• Are allergic to riboflavin or any ingredients in the solution
• Have had cataract surgery and don't have a UV-blocking intraocular lens
• Have never had a natural lens in your eye (aphakic)

Corneal Thickness Requirement

Your cornea must be at least 325 microns thick to safely undergo the procedure. If it's thinner, UV-A irradiation will not be performed to avoid potential damage to deeper eye structures.

Tell your eye doctor about:

• All eye conditions you have or have had
• Any history of herpes simplex eye infections
• Previous eye surgeries, especially cataract surgery
• Whether you wear contact lenses
• All medications and eye drops you currently use
• Any allergies to medications or preservatives
• Whether you are pregnant, planning to become pregnant, or breastfeeding.

Pregnancy and breastfeeding

There is limited information about using Epioxa during pregnancy or while breastfeeding. Discuss the potential risks and benefits with your doctor.

Contact lenses

You may need to stop wearing contact lenses before the procedure. Follow your doctor's instructions about when you can resume wearing them after treatment.

Epioxa HD:

• 0.239% riboflavin 5'-phosphate ophthalmic solution
• Supplied in single-dose glass syringes

Epioxa:

• 0.177% riboflavin 5'-phosphate ophthalmic solution
• Supplied in single-dose glass syringes

Both formulations are preservative-free and intended for single use only during the cross-linking procedure.

Common side effects

The most common side effect reported in clinical trials was eye redness (conjunctival hyperemia), occurring in about 31% of patients.

Other side effects occurring in 5% to 25% of treated eyes included:

• Corneal haze (cloudy appearance)
• Light sensitivity (photophobia)
• Punctate keratitis (small spots of corneal inflammation)
• Eye pain
• Eye irritation
• Increased tearing
• Corneal epithelium defect (surface layer damage)
• Eyelid swelling
• Corneal striae (stress lines in the cornea)
• Reduced visual clarity
• Dry eye
• Anterior chamber flare (inflammation inside the eye).

Most side effects are temporary and resolve as your cornea heals.

Epioxa is applied only by an eye care professional during an in-office procedure. You cannot use this medication at home.

The procedure typically involves:

Preparation:

• Numbing drops are applied to your eye
• A device (lid speculum) keeps your eyelid open
• The surface of your cornea is gently cleaned without removing the outer cell layer.

Epioxa HD Application (STEP 1):

• Two drops applied every 60 seconds for 4 minutes

Epioxa Application (STEP 2):

• Two drops applied every 30 seconds for 6 minutes

Before UV-A Treatment:

• Your cornea is rinsed with balanced salt solution
• Corneal thickness is measured (must be at least 325 microns to proceed safely)
• Boost Goggles are applied, and the oxygen flow is turned on.

UV-A Light Treatment:

• The O2n System delivers controlled UV-A light for about 11 minutes
• Light cycles on and off (1 second on, 1 second off)
• Moisturizing drops are applied every 2 minutes during treatment.

After Treatment:

• Goggles and lid speculum are removed
• A protective bandage contact lens is placed on your eye.

Total procedure time: Approximately 30-45 minutes.

After corneal cross-linking with Epioxa, you may experience:

• Eye redness and irritation
• Light sensitivity
• Tearing
• Mild to moderate eye pain or discomfort
• Blurred vision temporarily
• Feeling like something is in your eye.

Your doctor will provide specific aftercare instructions and may prescribe:

• Antibiotic eye drops to prevent infection
• Anti-inflammatory drops
• Lubricating eye drops
• Pain medication if needed.

The bandage contact lens typically stays in place for several days while your cornea heals.

Epioxa is stored and handled by your eye care professional. It is not dispensed for home use.

O2n System

A specialized medical device that delivers precisely controlled UV-A light (wavelength 365 nm) to your cornea. The device automatically manages the treatment duration and light intensity.

Boost Goggles

Special goggles that deliver oxygen to the cornea during UV-A irradiation. Oxygen enhances the cross-linking process and may improve treatment outcomes.

Your doctor will operate this equipment according to the manufacturer's guidelines.

Vision improvement and corneal stabilization occur gradually over several months following the procedure. You may notice:

• Initial vision fluctuation during the first few weeks
• Gradual vision improvement over 3-6 months
• Corneal shape stabilization over 6-12 months.

Your doctor will monitor your progress with regular follow-up appointments to assess:

• Corneal shape and curvature
• Visual acuity
• Signs of keratoconus progression
• Overall eye health.

Most patients experience stabilization of their keratoconus, meaning it stops getting worse. Some patients notice improved vision, though results vary.

Report side effects: Contact your eye doctor immediately if you experience:

• Severe eye pain
• Sudden vision loss
• Signs of infection (increased redness, discharge, swelling)
• Worsening symptoms after several days.

You can also report side effects to:

• Glaukos Corporation: 1-888-404-1644
• FDA MedWatch: 1-800-FDA-1088 or www.fda.gov/medwatch