Cystagon Side Effects

Generic name: cysteamine

Medically reviewed by Drugs.com. Last updated on May 15, 2024.

Note: This document provides detailed information about Cystagon Side Effects associated with cysteamine. Some dosage forms listed on this page may not apply specifically to the brand name Cystagon.

Applies to cysteamine: oral capsule, oral capsule delayed release, oral packet.

Serious side effects of Cystagon

Along with its needed effects, cysteamine (the active ingredient contained in Cystagon) 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 while taking cysteamine:

Other side effects of Cystagon

Some side effects of cysteamine 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:

Precautions

It is important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests and eye exams will be needed to check for unwanted effects.

Using high doses of this medicine may cause a condition called Ehler-Danlos-like syndrome. Check with your doctor right away if you have unusual changes on your skin and bones, including bone pain, tenderness, or aching, curved spine, loss of appetite, stretch marks, broken bones, joint problems, or unusual weight loss.

Serious skin reactions (eg, erythema multiforme bullosa, toxic epidermal necrolysis) can occur with this medicine. Check with your doctor right away if you have blistering, peeling, or loosening of the skin, chills, cough, diarrhea, itching, joint or muscle pain, red irritated eyes, red skin lesions, sore throat, sores, ulcers on the skin, or white spots in the mouth or on the lips, or unusual tiredness or weakness while you are using this medicine.

This medicine may cause stomach or bowel ulcers or bleeding. Check with your doctor right away if you have severe stomach pain, nausea, vomiting, loss of appetite, or if you are vomiting blood that looks like coffee grounds.

Check with your doctor right away if you have bloody or persistent diarrhea, loss of bowel control, stomach pain, or vomiting. These may be symptoms of fibrosing colonopathy.

This medicine may affect how your brain is working. Tell your doctor right away if you develop seizures, depression, or if you become very sleepy while taking this medicine.

Check with your doctor right away if you have bulging soft spot on the head of an infant, change in ability to see colors, especially blue or yellow, dizziness, headache, hearing loss, continued ringing in the ears, nausea, blurred or double vision, loss of vision, pain behind the eyes, or pain with eye movement. These may be symptoms of benign intracranial hypertension.

This medicine will lower the number of some types of blood cells in your body. Because of this, you may get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often.

This medicine may cause some people to become dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

Do not drink alcohol while you are using this medicine.

It is important to tell your doctor right away if you are pregnant or have become pregnant while using this medicine.

For healthcare professionals

Applies to cysteamine: oral capsule, oral delayed release capsule, oral granule enteric coated.

General adverse events

The most common adverse events were vomiting, abdominal pain, nausea, anorexia, fever, diarrhea, lethargy, headache, and rash.^[Ref]

Gastrointestinal

• Very common (10% or more): Vomiting (35%), diarrhea (16%)
• Common (1% to 10%): Nausea, bad breath, abdominal pain, dyspepsia
• Uncommon (0.1% to 1%): Gastrointestinal ulceration and bleeding, constipation, gastroenteritis, duodenitis^[Ref]

Metabolic

• Very common (10% or more): Anorexia (31%)
• Uncommon (0.1% to 1%): Dehydration^[Ref]

Nervous system

• Very common (10% or more): Lethargy (11%)
• Common (1% to 10%): Dizziness, headache, encephalopathy
• Uncommon (0.1% to 1%): Somnolence, seizures, convulsions, ataxia, confusion, tremor, hyperkinesia, jitteriness
• Postmarketing reports: Benign intracranial hypertension with papilledema^[Ref]

Other

• Very common (10% or more): Fever (22%)
• Common (1% to 10%): Fatigue, asthenia
• Uncommon (0.1% to 1%): Decreasing hearing^[Ref]

Dermatologic

• Common (1% to 10%): Rash, skin odor
• Uncommon (0.1% to 1%): Hair color changes, skin fragility (molluscoid pseudomotor on elbows)
• Frequency not reported: Urticaria
• Postmarketing reports: Skin lesions, skin striae, skin fragility^[Ref]

Cases of Ehlers-Danlos like syndrome and vascular disorders on elbows have been reported in children chronically treated with high doses of different cysteamine preparations. In cases where histopathological examination of the skin was performed, the results suggested angioendotheliomatosis.^[Ref]

Hepatic

• Common (1% to 10%): Abnormal liver function
• Frequency not reported: Elevated alkaline phosphatase^[Ref]

Cardiovascular

• Uncommon (0.1% to 1%): Hypertension^[Ref]

Genitourinary

• Uncommon (0.1% to 1%): Abnormal urine odor^[Ref]

Hematologic

• Uncommon (0.1% to 1%): Leukopenia, anemia^[Ref]

Immunologic

• Uncommon (0.1% to 1%): Anaphylactic reaction^[Ref]

Musculoskeletal

• Uncommon (0.1% to 1%): Joint hyperextension, leg pain, genu valgum, osteopenia, compression fracture, scoliosis
• Postmarketing reports: Molluscoid pseudotumors^[Ref]

Psychiatric

• Uncommon (0.1% to 1%): Nervousness, abnormal thinking, depression, emotional lability, hallucinations, nightmares^[Ref]

Renal

• Uncommon (0.1% to 1%): Nephrotic syndrome, interstitial nephritis, renal failure^[Ref]

Cases of nephrotic syndrome have been reported within 6 months of starting therapy with progressive recovery after treatment discontinuation. In some cases, histology showed a membranous glomerulonephritis of the renal allograft and hypersensitivity interstitial nephritis.^[Ref]

See also:

Further information

Cystagon side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer