Cysteamine (By mouth)


Cysteamine (sis-TEE-a-meen)

Prevents buildup of cystine crystals in the kidneys.

Brand Name(s)

Cystagon, Procysbi

When This Medicine Should Not Be Used

How to Use This Medicine

Capsule, Delayed Release Capsule

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
  • Immediate-release capsule (Cystagon┬«):
    • If your child is using this medicine, you may open the immediate-release capsule and mix it in your child's food.
  • Delayed-release capsule (Procysbi?):
    • Swallow the delayed-release capsule whole. Do not crush or chew the capsule or contents of the capsule.
    • Take this medicine the same way every day. This means take it at the same time and take it consistently, either with or without food. Do not eat high-fat food near the time that you take this medicine.
      • Without food: It is best to take this medicine on an empty stomach. Take it at least 30 minutes before a meal or at least 2 hours after a meal.
      • With food: If you must eat, you can eat a small amount of food (1/2 cup) between 1 hour before or after you take Procysbi?.
    • If you cannot swallow the capsule whole, you may open it and take the capsule contents only with certain foods and juices:
      • Applesauce or berry jelly: Open the capsule and sprinkle the granules on 4 ounces (1/2 cup) of applesauce or berry jelly. Swallow the entire mixture within 30 minutes.
      • Apple juice or orange juice: Open the capsule and sprinkle the granules into 4 ounces (1/2 cup) of apple juice or orange juice. Shake this mixture gently for 5 minutes. Drink it within 30 minutes.
      • Feeding tube: Open the capsule and sprinkle the granules on 4 ounces (1/2 cup) of applesauce. Mix and give the mixture through the feeding tube within 30 minutes. Flush the tube with 8 ounces (1 cup) of apple juice or orange juice. Do not use other liquids to flush the tube.
    • Missed dose:
      • Immediate-release (Cystagon┬«): If it is less than 2 hours until your next dose, wait until then and take your normal dose at the normal time. If it is more than 2 hours, take the missed dose as soon as you can. Never take extra medicine to make up for the missed dose.
      • Delayed-release (Procysbi?): If it is less than 4 hours until your next dose, wait until then and take your normal dose at the normal time. If it is more than 4 hours, take the missed dose as soon as you can. Never take extra medicine to make up for the missed dose.
    • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Store the delayed-release capsules in the original container. Keep it in a dry place away from light.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

Warnings While Using This Medicine

  • Tell your doctor if you are pregnant or breastfeeding, or if you have liver disease, ulcers or bleeding in your stomach or intestines, or a history of head injury, depression, or seizures.
  • This medicine may cause the following problems:
    • Skin, joint, or bone problems
    • Gastrointestinal bleeding
    • Central nervous system symptoms, such as severe sleepiness or seizures
    • Benign intracranial hypertension
  • This medicine may make you dizzy or drowsy. Do not drive or doing anything else that could be dangerous until you know how this medicine affects you.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blistering, peeling, or red skin rash
  • Bloody vomit or black, tarry stools
  • Bone, joint, or leg pain
  • Depression, severe sleepiness, seizures
  • Fever, chills, cough, sore throat, and body aches
  • Red-purple lines on your arms, face, legs, trunk, or groin
  • Severe headache, vision problems
  • Severe stomach pain, nausea, vomiting, loss of appetite
  • Unusual bleeding, bruising, or weakness

If you notice these less serious side effects, talk with your doctor:

  • Mild headache
  • Mild nausea, vomiting, constipation, diarrhea, stomach upset
  • Mild skin rash or itching
  • Tiredness

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last reviewed on 8/4/2014

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