In the U.S.—

In Canada—

Other commonly used names are cromoglicic acid; cromoglycic acid; sodium cromoglycate.

• Antiallergic, ophthalmic
• Mast cell stabilizer, ophthalmic

Cromolyn ( KROE-moe-lin) ophthalmic solution is used in the eye to treat certain disorders of the eye caused by allergies. It works by acting on certain cells, called mast cells, to prevent them from releasing substances that cause the allergic reaction.

Cromolyn is available only with your doctor's prescription, in the following dosage form:

Ophthalmic
• Ophthalmic solution (eye drops) (U.S. and Canada)

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For ophthalmic cromolyn, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to cromolyn. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Cromolyn has not been studied in pregnant women. Studies in animals have shown that cromolyn causes a decrease in successful pregnancies and a decrease in the weight of the animal fetus when given by injection in very large amounts. However, it is unlikely that ophthalmic cromolyn will cause problems in humans when used in the eye as directed.

Breast-feeding—It is not known whether cromolyn passes into the breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of cromolyn in children up to 4 years of age with use in other age groups. For older children, this medicine is not expected to cause different side effects or problems than it does in adults.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. Although there is no specific information comparing use of ophthalmic cromolyn in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than it does in younger adults.

To use the eye drops:

• First, wash your hands. Tilt the head back and, pressing your finger gently on the skin just beneath the lower eyelid, pull the lower eyelid away from the eye to make a space. Drop the medicine into this space. Let go of the eyelid and gently close the eyes. Do not blink. Keep the eyes closed for 1 or 2 minutes to allow the medicine to be absorbed by the eye.
• If you think you did not get the drop of medicine into your eye properly, use another drop.
• To keep the medicine as germ-free as possible, do not touch the applicator tip to any surface (including the eye). Also, keep the container tightly closed.

Use cromolyn eye drops only as directed. Do not use more of this medicine and do not use it more often than your doctor ordered. To do so may increase the chance of side effects.

In order for this medicine to work properly, it must be used every day in regularly spaced doses as ordered by your doctor. A few days may pass before you begin to feel better. However, in some conditions, it may take several weeks before you begin to feel better.

Dosing—

The dose of ophthalmic cromolyn will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of ophthalmic cromolyn. If your dose is different, do not change it unless your doctor tells you to do so.

• For ophthalmic solution (eye drops) dosage form:
  • For eye allergies:
    • Adults and children 4 years of age and older—Use one drop four to six times a day in regularly spaced doses.
    • Children up to 4 years of age—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, use it as soon as possible. Then go back to your regular dosing schedule.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Keep the medicine from freezing.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

If your symptoms do not improve or if your condition becomes worse, check with your doctor.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• Rare
  • Rash or redness around the eyes;  swelling of the membrane covering the white part of the eye, redness of the white part of the eye, styes, or other eye irritation not present before therapy 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Burning or stinging of eye (mild and temporary) 
  
  

• Less common or rare
  • Dryness or puffiness around the eye;  watering or itching of eye (increased) 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.