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Generic Name: cysteamine ophthalmic (sis TEE a meen off THAL mik)
Brand Names: Cystaran

Medically reviewed by Last updated on Apr 23, 2020.

What is Cystaran?

Cystaran (cysteamine) works by reducing the amount of cystine (an amino acid) in the body. Cysteamine is used in children with nephropathic cystinosis, a rare genetic condition that causes a build-up of cystine in the kidneys and other organs. Too much cystine can cause kidney failure or other medical problems.

Cystaran eye drops are used to keep cystine crystals from building up in the cornea (surface of the eye).

Important information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not use Cystaran eye drops if you are allergic to cysteamine.

It is not known whether Cystaran will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medicine.

It is not known whether cysteamine ophthalmic passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using Cystaran.

How should I use Cystaran?

Cystaran eye drops are usually given once every hour while you are awake. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Do not take by mouth. Cystaran is for use only in the eyes.

Wash your hands before using the eye drops.

To apply the Cystaran eye drops:

  • Tilt your head back slightly and pull down your lower eyelid to create a small pocket. Hold the dropper above the eye with the tip down. Look up and away from the dropper and squeeze out a drop.

  • Close your eyes for 2 or 3 minutes with your head tipped down, without blinking or squinting. Gently press your finger to the inside corner of the eye for about 1 minute, to keep the liquid from draining into your tear duct.

  • Use only the number of drops your doctor has prescribed.

  • Wait at least 10 minutes before using any other eye drops your doctor has prescribed.

Do not touch the tip of the eye dropper or place it directly on your eye. A contaminated dropper can infect your eye, which could lead to serious vision problems.

Do not use the eye drops if the liquid has changed colors or has particles in it. Call your pharmacist for a new supply of Cystaran.

Each bottle of Cystaran should be kept in a freezer until you are ready to start using it.

Thaw the medicine for 24 hours before your first use. Then store at room temperature away from moisture and heat. Do not refreeze after thawing.

Throw away the bottle after 1 week of use. Be sure to remove a new bottle from the freezer in time to allow 24 hours for thawing. When you take a bottle out of the freezer, write the discard date (7 days after first use) on the bottle so you will know when to throw it away.

Cystaran dosing information

Usual Adult Dose for Corneal Cystine Crystal Accumulation:

Recommended dose: 1 drop in each eye, every waking hour.

What happens if I miss a dose?

Use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

What happens if I overdose?

An overdose of cysteamine is not expected to be dangerous. Seek emergency medical attention or call the Poison Help line at 1-800-222-1222 if anyone has accidentally swallowed the medication.

What should I avoid while using Cystaran?

Do not use this medicine while wearing soft contact lenses. A preservative in the medicine could discolor the lenses. Wait at least 15 minutes after using this medicine before inserting your contact lenses.

Cystaran side effects

Get emergency medical help if you have any signs of an allergic reaction to Cystaran: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • increased pressure inside the skull - severe headaches, ringing in your ears, dizziness, nausea, vision problems, pain behind your eyes.

Common Cystaran side effects may include:

  • eye pain, redness, or irritation;

  • headache;

  • vision problems; or

  • increased sensitivity of your eyes to light.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Cystaran?

It is not likely that other drugs you take orally or inject will have an effect on cysteamine used in the eyes. But many drugs can interact with each other. Tell each of your healthcare providers about all medicines you use, including prescription and over-the-counter medicines, vitamins, and herbal products.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Cystaran only for the indication prescribed.

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