Locations:

Cysteamine Capsules

What is this medication?

CYSTEAMINE (sis TEE a meen) treats the buildup of cystine crystals in the body. It works by decreasing the amount of the amino acid cystine in the body. This prevents crystals from forming, which prevents or delays worsening symptoms.

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This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Cystagon

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Blood diseases
  • Bone problems
  • Depression or other mental health conditions
  • Frequently drink alcohol
  • Liver disease
  • Seizures
  • Skin conditions
  • Stomach or intestine problems
  • An unusual or allergic reaction to cysteamine, penicillamine, other medications, foods, dyes, or preservatives
  • Pregnant or trying to get pregnant
  • Breastfeeding

How should I use this medication?

Take this medication by mouth with water. Take it as directed on the prescription label at the same time every day. Do not cut, crush, or chew this medication. Swallow the capsules whole. You may open the capsule and put the contents on food. Swallow the medication and food right away. Do not chew.

Talk to your care team about the use of this medication in children. While this medication may be prescribed for selected conditions, precautions do apply.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is within 2 hours of your next dose, take only that dose. Do not take double or extra doses.

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What may interact with this medication?

Interactions are not expected.

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress. Tell your care team if your symptoms do not start to get better or if they get worse. You may need blood work while you are taking this medication.

This medication may affect your coordination, reaction time, or judgment. Do not drive or operate machinery until you know how this medication affects you. Sit up or stand slowly to reduce the risk of dizzy or fainting spells.

This medication may cause serious skin reactions. They can happen weeks to months after starting the medication. Contact your care team right away if you notice fevers or flu-like symptoms with a rash. The rash may be red or purple and then turn into blisters or peeling of the skin. You may also notice a red rash with swelling of the face, lips, or lymph nodes in your neck or under your arms.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Dizziness, loss of balance or coordination, confusion or trouble speaking
  • Increased pressure around the brain—severe headache, blurry vision, change in vision, nausea, vomiting
  • Joints that stretch farther than usual, soft, stretchy skin, unusual bruising
  • Redness, blistering, peeling, or loosening of the skin, including inside the mouth
  • Seizures
  • Stomach bleeding—bloody or black, tar-like stools, vomiting blood or brown material that looks like coffee grounds
  • Sudden or severe stomach pain, bloody diarrhea, fever, nausea, vomiting
  • Worsening mood, feelings of depression

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

  • Bad breath
  • Diarrhea
  • Loss of appetite
  • Nausea
  • Stomach pain
  • Unusual weakness or fatigue
  • Vomiting

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Get rid of any unused medication after the expiration date.

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To get rid of medications that are no longer needed or have expired:

  • Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
  • If you cannot return the medication, check the label or package insert to see if the medication should be thrown out in the garbage or flushed down the toilet. If you are not sure, ask your care team. If it is safe to put it in the trash, empty the medication out of the container. Mix the medication with cat litter, dirt, coffee grounds, or other unwanted substance. Seal the mixture in a bag or container. Put it in the trash.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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