Health Library

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, Packet

• 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 with food.
• Delayed-release capsule or granules (Procysbi®):
  • Swallow the capsule whole. Do not crush or chew the capsule or the contents.
  • 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 close to the time that you will 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: You may have a small amount of food (1/2 cup) between 1 hour before and 1 hour after you take this medicine.
  • If you cannot swallow the capsule or granules whole, you may open it and mix the contents only with certain foods and fruit juices or water.
    • Applesauce or berry jelly: Open the capsule or packet and sprinkle the granules with 4 ounces (1/2 cup) of applesauce or berry jelly. Mix the granules with food. Swallow the entire mixture within 30 minutes. Do not chew the granules. Do not save the applesauce or berry jelly and granules for later use.
    • Fruit juice (except grapefruit juice): Open the capsule or packet and sprinkle the granules to 4 ounces (1/2 cup) of fruit juice. Gently stir to mix. Drink the mixture within 30 minutes. Do not chew the granules. Do not save the fruit juice or granules for later use.
    • Feeding tube: Open the capsule or packet and sprinkle the granules with 4 ounces (1/2 cup) of strained applesauce. For children receiving 1 or 2 capsules, use a minimum of 1 ounce of applesauce. Use only strained applesauce with no chunks. Mix and give the medicine through the gastrostomy tube into the stomach within 30 minutes. Flush the tube with 10 milliliters (mL) of fruit juice or water. Do not save the mixture for later use.
  • Follow any special instructions from your doctor, including taking dietary supplements, vitamin D, and thyroid hormone medicine. These supplements will replace minerals lost through the kidneys.
• Missed dose:
  • Immediate-release (Cystagon®): If it is more than 2 hours until your next dose, take the missed dose as soon as you can. If it is less than 2 hours, skip the missed dose and take your normal dose at the regular time. Do not take extra medicine to make up for the missed dose.
  • Delayed-release (Procysbi®): You may take a missed dose as soon as you can up to 8 hours after your scheduled dose. If it is less than 4 hours, skip the missed dose and take your normal dose at the regular time. Do not take 2 doses at one time 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.

• Take Procysbi® at least 1 hour before or after you take medicines that contain bicarbonate or carbonate.
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have liver disease, bone problems, stomach or bowel problems, or a history of blood problems, head injury, depression, or seizures.
• This medicine may cause the following problems:
  • Skin, joint, or bone problems, including Ehler-Danlos-like syndrome
  • Serious skin reactions, including erythema multiforme bullosa, toxic epidermal necrolysis
  • Stomach or bowel problems, including ulcers, bleeding, fibrosing colonopathy
  • Benign intracranial hypertension (increased pressure inside your head)
• This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
• This medicine lowers the number of white blood cells. This weakens your immune system, so you may get infections more easily. Wash your hands often. Avoid people who are sick.
• 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, red skin rash
• Bloody vomit, black, tarry stools
• Bone, joint, or leg pain
• Depression, severe sleepiness, seizures
• Fever, chills, cough, sore throat, body aches
• Severe headache, vision problems, ringing or buzzing in your ears
• Severe stomach pain, diarrhea, nausea, vomiting, loss of appetite
• Skin changes, easy bruising, red or purple lines on your skin

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

• Headache
• Mild nausea, vomiting, stomach upset
• 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

Last Updated: 9/6/2024