Medically reviewed by Drugs.com. Last updated on Feb 23, 2022.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
Therapeutic Class: Ophthalmologic Agent
Uses for cysteamine
Cysteamine eye drops is used to treat cystine crystal buildup in the cornea (front part of the eye) of patients with cystinosis. Cystinosis is a hereditary disorder that causes an accumulation of the amino acid cystine within cells, forming crystals that can build up and damage the eyes. Cysteamine works by removing the extra cystine from the cornea.
Cysteamine is available only with your doctor's prescription.
Before using cysteamine
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For cysteamine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to cysteamine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of cysteamine eye drops in children.
Although appropriate studies on the relationship of age to the effects of cysteamine eye drops have not been performed in the geriatric population, no geriatric-specific problems have been documented to date.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using cysteamine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use cysteamine, or give you special instructions about the use of food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of cysteamine. Make sure you tell your doctor if you have any other medical problems, especially:
- Brain disease or
- Head injury, history of or
- Increased pressure in the head—Use with caution. May make these conditions worse.
Proper use of cysteamine
Your eye doctor will tell you how much of cysteamine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
If you or your child are wearing contact lenses, remove them before you use cysteamine eye drops. Wait for at least 15 minutes before putting the contact lenses back in. Talk to your eye doctor about this if you have questions.
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.
- Immediately after using the eye drops, wash your hands to remove any medicine that may be on them.
- To keep the medicine as germ-free as possible, do not touch the applicator tip to any surface (including the eye). Also, always keep the container tightly closed.
Wait at least 10 minutes before using other eye products.
The dose of cysteamine 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 cysteamine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For cystine crystal buildup in the cornea:
- For ophthalmic dosage form (Cystadrops® eye drops):
- Adults and children—Use one drop in each eye 4 times a day, during waking hours.
- For ophthalmic dosage form (Cystaran™ eye drops):
- Adults and children—Use one drop in each eye, every waking hour.
- For ophthalmic dosage form (Cystadrops® eye drops):
If you miss a dose of cysteamine, apply it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Store the new, unopened Cystadrops® bottle in its original carton in the refrigerator. After first opening, keep medicine at room temperature. Protect from light. Do not refrigerate after opening. Throw away any unused medicine after 7 days.
Store the Cystaran™ bottle in its original carton in the freezer. Allow the bottle to reach room temperature before use. You may store the thawed bottle in the refrigerator or at room temperature. Do not refreeze. Throw away any unused medicine after 7 days.
Precautions while using cysteamine
Your eye doctor will check your or your child's eyes at regular visits to make sure it is working properly and is not causing unwanted effects.
If your or your child's symptoms do not improve within a few days or if they become worse, check with your doctor.
If you hurt your eye, develop an eye infection, or need to have eye surgery, talk with your doctor right away. You or your child may need to change your medicine or stop using it.
Cysteamine side effects
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 immediately if any of the following side effects occur:
- Blurred vision
- decrease or change in vision
- eye pain, redness, itching, irritation, or swelling
- sensitivity of the eyes to light
Some 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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Watering of the eyes
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about cysteamine ophthalmic
- Side effects
- Dosage information
- During pregnancy
- Compare alternatives
- En español
- Drug class: miscellaneous ophthalmic agents
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.