In the U.S.—

• Nephropathic cystinosis therapy

Cysteamine (sis-TEE-a-meen) is used to prevent damage that may be caused by the buildup of cystine crystals in organs such as the kidneys. This medicine works by removing the extra cystine from the cells of the body.

Oral
• Capsules (U.S.)

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:

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

Pregnancy—Cysteamine has not been studied in pregnant women. However, studies in animals have shown that cysteamine causes a decrease in fertility and a decrease in survival of their offspring. Before taking this medicine, make sure your health care professional knows if you are pregnant or if you may become pregnant.

Breast-feeding—It is not known whether cysteamine passes into breast milk. Since cysteamine has been reported to cause problems in nursing animals, it may be necessary for you to stop taking this medicine or to stop breast-feeding during treatment.

Children—This medicine has been tested in children and, in effective doses, has not been shown 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 or if they cause different side effects or problems in older people. There is no specific information comparing use of cysteamine in the elderly with use in other age groups.

• Blood problems (or a history of) or
• Convulsions (seizures) or
• Liver disease—Cysteamine may make these conditions worse

If you vomit your dose of cysteamine within 20 minutes of taking it, take the dose again. However, if you vomit the dose a second time, do not repeat the dose but wait and take your next dose as scheduled. Also, if vomiting occurs more than 20 minutes after you take your dose, do not repeat the dose.

It is important that you follow any special instructions from your doctor, such as taking dietary supplements. These supplements will replace minerals lost through the kidneys.

For children under 6 years of age, the capsule may be opened and the contents of the capsule sprinkled on food or mixed in formula.

Dosing—

The dose of cysteamine will be different for different patients. Follow your health care professional'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 health care professional tells you to do so.

• For oral dosage form (capsules):
  • To prevent buildup of cystine crystals in the kidney:
    • Adults and teenagers—The starting dose must be determined by your doctor. Your doctor may gradually increase your dose.
    • Children—The starting dose is based on body size and must be determined by your doctor. Your doctor may gradually increase your dose.

Missed dose—

If you miss a dose of this medicine, take 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. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Keep the medicine from freezing. Do not refrigerate.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Your doctor should check your progress at regular visits to make sure that this medicine is working properly and does not cause unwanted effects.

This medicine may cause some people to become dizzy or drowsy. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert.

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:

• More common
  • Abdominal pain;  diarrhea;  drowsiness;  fever;  loss of appetite;  nausea or vomiting;  skin rash 
  
  

• Less common
  • Confusion;  dizziness;  headache;  mental depression;  sore throat;  trembling 
  
  

• Rare
  • Convulsions (seizures);  increased thirst ;  unusual tiredness or weakness 
  
  

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:

• Less common
  • Breath odor;  constipation 
  
  

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