Keratoconus Medication

Updated: Jan 04, 2023
  • Author: Karen K Yeung, OD, FAAO; Chief Editor: Hampton Roy, Sr, MD  more...
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Medication Summary

The only FDA-approved medication to treat the progression of keratoconus is riboflavin 5´-phosphate ophthalmic solution. It is a photoenhancer indicated for use with ultraviolet (UV) A exposure in the procedure for corneal collagen cross-linking (CXL).

Antihistamine/mast cell–stabilizing topical medications, antihistamines, mast cell stabilizers, nonsteroidal anti-inflammatory (NSAID), and, occasionally, steroids are helpful in controlling the often concomitant signs of ocular allergies, especially pruritus, that can lead to eye rubbing. These medications can also help with giant papillary conjunctivitis, which is a common complication of contact lens wear. Steroids should be used only after consideration of increased risks of cataracts, glaucoma, and decreased ability to resist infection. Cyclosporine ophthalmic emulsion is helpful in managing the inflammatory and dry-eye components of the disease.

Episodes of hydrops may require treatment with hyperosmotics to reduce corneal swelling or topical steroid drops to reduce inflammation. Topical antibiotics are used for suspected infection.



Class Summary

Under the conditions used for corneal collagen cross-linking, riboflavin 5´-phosphate functions as a photoenhancer and generates singlet oxygen, which is responsible for the cross-linking. Riboflavin and UVA corneal CXL elicits a stiffening effect on the corneal stroma, which increases its biomechanical strength, thus enabling the arrest of the progression of the disease.

Riboflavin 5'-phosphate ophthalmic (Photrexa, Photrexa Viscous)

Riboflavin 5´-phosphate sodium (vitamin B2) is the precursor of 2 coenzymes, flavin adenine dinucleotide and flavin mononucleotide, which catalyze oxidation/reduction reactions involved in a number of metabolic pathways. It is indicated for use in corneal collagen cross-linking in combination with the KXL System for the treatment of progressive keratoconus. Both the viscous solution (in 20% dextran) and the regular solution are used topically during the corneal CXL procedure.


Antihistamines/Mast cell stabilizer, ophthalmic

Class Summary

Mast cell stabilizers treat the long-term phases of ocular allergies and specifically giant papillary conjunctivitis (GPC), which can result from contact lens wear. GPC primarily appears to be a Gel-Coombs type 1 hypersensitivity disease. The primary pathological event is inappropriate degranulation of the conjunctival mast cells, which release many inflammatory mediators, such as histamine (resulting in itch). Pure mast cell stabilizers are indicated for long-term use after the acute phase of symptoms abates. They are well tolerated. Symptoms may include burning. Their four-times-a-day dosing decreases the rate of compliance and may result in treatment failure.

Azelastine 0.05% (Optivar)

Antihistamine and mast cell stabilizer.

Alcaftadine ophthalmic (Lastacaft)

Alcaftadine is an H1-receptor antagonist. It inhibits histamine release from mast cells, decreases chemotaxis, and inhibits eosinophil activation. Lastacaft is dosed at once a day to improve patient compliance.

Bepotastine (Bepreve)

Bepreve is a histamine H1 receptor antagonist indicated for the treatment of itching associated with allergic conjunctivitis. It is dosed twice a day in each eye.

Epinastine (Elestat)

Epinastine is a direct histamine-1 receptor antagonist. It is indicated for symptoms due to allergic conjunctivitis. Its recommended dosage is twice a day.

Ketotifen fumarate 0.0.25% (Zaditor, Alaway, Claritin Eye, GoodSense Itchy Eye, Eye Itch Relief)

Ketotifen is a relatively selective, noncompetitive H1-receptor antagonist and inhibitor of histamine release from mast cells. This is an over-the-counter product. Recommended frequency is twice a day.

Olopatadine ophthalmic (Pataday, Patanol, Pazeo)

Olopatadine is a histamine H1 receptor antagonist that inhibits the release of histamine from mast cells and histamine-induced effects on conjunctival epithelial cells. Pazeo's recommended dosing is once a day, which can improve patient compliance.


Mast cell stabilizers

Class Summary

These agents are used to manage signs and symptoms of long-term ocular allergies, which can lead to patient discomfort and increased vigorous eye rubbing.

Cromolyn sodium

Cromolyn sodium is a mast cell stabilizer that inhibits histamine and SRS-A from mast cells. It was the first drug of its class. Its recommended dosage is four times a day.

Nedocromil sodium (Alocril)

Nedocromil inhibits the release of various inflammatory cell mediators (mast cell stabilizer). It has greater efficacy than cromolyn sodium. Its recommended dosage is twice a day.

Pemirolast ophthalmic (Alamast)

Pemirolast is a mast cell stabilizer indicated for the prevention of itching due to allergic conjunctivitis. Its recommended dosage is four times a day.


Second generation antihistamines

Class Summary

These agents inhibit many aspects of the inflammatory response from inciting agents: edema, capillary dilation and proliferation, leukocyte migration, and fibroblast proliferation.

Azelastine ophthalmic (Optivar)

Azelastine ophthalmic is a selective H1-receptor competitor with H1-receptor sites on effector cells. It also exhibits H2-blocking properties. It inhibits the release of histamine and other mediators involved in the allergic response. Its recommended dosage is twice a day.

Emedastine (Emadine)

Emedastine difumarate is a relatively selective H1 receptor antagonist that appears to be devoid of effects on adrenergic, dopaminergic, and serotonin receptors. It affects both the early and late phases of the ocular allergic reaction. Its recommended dosage is four times a day.



Class Summary

These agents have anti-inflammatory properties and cause profound and varied metabolic effects. They modify the body's immune response to diverse stimuli. They are used to manage ophthalmic inflammation of giant papillary conjunctivitis resulting from keratoconus and contact lens wear.

Loteprednol etabonate (Lotemax, Alrex)

Loteprednol modulates the activity of prostaglandins and leukotrienes. Placebo-controlled studies have demonstrated that loteprednol reduces the signs and symptoms of GPC after 1 week of treatment, continuing for up to 6 weeks while on treatment. It has a reduced risk of increasing the intra-ocular pressure by rapidly converting into inactive metabolites after corneal penetration. Its recommended dosage is four times a day.


Hyperosmolar diuretics

Class Summary

These agents may reduce inflammation in cornea by creating an osmotic gradient across an intact blood barrier.

Sodium chloride hypertonic, ophthalmic (Muro 128, Altachlore, Sochlor)

Used for temporary relief of corneal edema during episodes of corneal hydrops. The solution is recommended to be used every 3-4 hours, and an ointment is recommended for nighttime use.



Class Summary

These agents may have anti-inflammatory effects.

Cyclosporine ophthalmic (Restasis)

Immunomodulator with anti- inflammatory effects. Used to manage dry eyes that accompany keratoconus and (off label) possible ocular inflammation associated with keratoconus. The drops are recommended to be used twice a day. If contact lenses are to be worn, wait 10-15 minutes before wearing contact lenses.