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CYSTEAMINE (sis TEE a meen) treats the buildup of cystine crystals in the eye. It works by decreasing the amount of the amino acid cystine in the eye. This prevents crystals from forming, which reduces eye pain and other symptoms.
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This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Cystadrops, CYSTARAN
They need to know if you have any of these conditions:
This medication is only for use in the eye. Follow the directions on the prescription label. Wash hands before and after use. Tilt your head back slightly and pull your lower eyelid down with your index finger to form a pouch. Try not to touch the tip of the dropper or tube to your eye, fingertips, or other surfaces. Squeeze the prescribed number of drops into the pouch. Close the eye gently to spread the drops. Do not use your medication more often than directed. Do not stop using except on the advice of your care team.
Talk to your care team about the use of this medication in children. While this medication may be prescribed for selected conditions, precautions do apply.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
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If you miss a dose, take it as soon as you can. If it is almost time for your next dose, use only that dose. Do not use double or extra doses.
Interactions are not expected. Do not use any other eye products without telling your care team.
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
Visit your care team for regular checks on your progress. Tell your care team if your symptoms do not start to get better or if they get worse.
Tell your care team right away if you have any change in your eyesight.
If you wear contact lenses, ask your care team when you can wear your lenses again.
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Keep out of the reach of children and pets.
See product for storage instructions. Each product may have different instructions.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.