cysteamine

Action and Spectrum

Actions and Spectrum:

• cysteamine is a potent antioxidant: cysteamine can scavenge free radicals and protect cells from oxidative stress.
• cysteamine is a mucolytic agent: cysteamine can break down mucus and improve airway clearance in people with cystic fibrosis.
• cysteamine is a neuroprotective agent: cysteamine can protect neurons from damage and promote nerve cell survival in various neurodegenerative disorders.
• cysteamine is an anti-inflammatory agent: Cysteamine can reduce inflammation in various tissues and organs, including the lungs and the skin.
• cysteamine is a chelating agent: cysteamine can bind to heavy metals and facilitate their excretion from the body.
• cysteamine is a pH-modifying agent: cysteamine can increase the pH of certain biological fluids, such as urine, and reduce the risk of crystal formation.
• cysteamine is a radiation-protective agent: cysteamine can protect cells and tissues from the damaging effects of ionizing radiation.

Drug Interaction

Adverse Reaction

Frequency defined:

>10%:

Diarrhea

Influenza

Abdominal pain

Fatigue

Dehydration

Arthralgia

Pain in extremities

Cough

Gastroenteritis

Nausea

1-10%:

Immediate release cysteamine

Anorexia/loss of appetite (5%)

Nausea (7%)

Delayed release cysteamine

Anorexia/loss of appetite (2%)

Dizziness (5%)

Black Box Warning

Contraindication / Caution

Contraindication/Caution:

Contraindications:

• Hypersensitivity: Individuals with a known hypersensitivity to cysteamine or any of its components should avoid using it.
• Gastrointestinal Disorders: cysteamine can cause nausea, vomiting, and abdominal pain in some individuals, particularly those with a history of gastrointestinal disorders.
• Liver and Kidney Disease: cysteamine is metabolized in the liver and excreted by the kidneys, so individuals with liver or kidney disease may be at a higher risk for adverse effects and should use cysteamine with caution.
• Pregnancy and breastfeeding: cysteamine may be harmful to a developing fetus or a breastfeeding baby, so it should be avoided during pregnancy and breastfeeding unless the potential benefits outweigh the risks.
• Drug Interactions: cysteamine may interact with other medications, including antacids, antibiotics, and immunosuppressants, and should be used cautiously in individuals taking these medications.
• Eye Irritation: cysteamine can cause eye irritation and should be avoided in individuals with pre-existing eye conditions.
• Skin Sensitivity: cysteamine can cause skin irritation and should be used cautiously in individuals with pre-existing skin conditions.

Pregnancy / Lactation

Pregnancy consideration:

No data is available regarding the usage of the drug in pregnant women.

Breastfeeding warnings:

No information is available regarding the excretion of the drug in breast milk.

Pregnancy category:

• Category A: well-controlled and satisfactory studies do not show risk to the fetus in the first/later trimester.      
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women.
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.
• Category D: adequate data available with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.
• Category N: No data is available for the drug under this category.

Pharmacology

Pharmacology:

cysteamine has a range of pharmacological actions that make it useful in various biomedical applications. Its effects on cystine depletion and lysosomal depletion are significant for treating cystinosis. In contrast, its antioxidant, neuroprotective, mucolytic, anti-inflammatory, and chelating effects make it a potential therapy for other conditions.

Pharmacodynamics:

• cysteamine is a cystine-depleting agent: cysteamine breaks down cystine, a component of cystine-rich proteins, into cysteine and cysteine-cysteamine mixed disulfides. This effect is the basis for its use in the treatment of cystinosis, a rare genetic disorder characterized by the accumulation of cystine in various organs and tissues.
• cysteamine is a lysosomal depleting agent: cysteamine can reduce the accumulation of lysosomal storage material by increasing lysosomal pH and promoting the export of lysosomal enzymes.
• cysteamine is an antioxidant: cysteamine can scavenge free radicals and protect cells from oxidative damage. It has been shown to reduce oxidative stress in various tissues, including the liver, brain, and lungs.
• cysteamine is a neuroprotective agent: cysteamine can protect neurons from damage and promote nerve cell survival. It has been shown to be effective in animal models of neurodegenerative disorders such as Huntington’s disease and Parkinson’s disease.
• cysteamine is a mucolytic agent: cysteamine can break down mucus and improve airway clearance in individuals with cystic fibrosis.
• cysteamine is an anti-inflammatory agent: cysteamine can reduce inflammation in various tissues and organs, including the lungs and the skin.
• cysteamine is a chelating agent: cysteamine can bind to heavy metals and facilitate their excretion from the body.

Pharmacokinetics:

The onset of action is 1-1.8 hours

Duration of action is 6-12 hours

Peak plasma is achieved in 1.4 hour

The volume of distribution is 156 L

Bioavailability is high

Protein Bound is 52% (mainly albumin)

A small amount of the drug is excreted in urine

Adminstartion

Administration:

The specific administration instructions for cysteamine may vary depending on the formulation and the condition being treated. Here are some general guidelines for the administration of cysteamine:

• Oral capsules: cysteamine capsules are usually taken orally, with or without food. The usual dose for cystinosis is 1.3 g/m²/day, divided into four doses, taken every six hours. However, the dose and dosing schedule may vary depending on the patient’s age, weight, and renal function.
• Delayed-release capsules: Delayed-release cysteamine capsules are designed to release the drug over a more extended period, allowing for less frequent dosing. These capsules are usually taken with or without food once or twice a day. The specific dose and dosing schedule may vary depending on the treated condition.
• Eye drops: cysteamine eye drops are used to treat corneal cystine crystals in patients with cystinosis. The drops are usually applied to the affected eye every waking hour. The dose and dosing schedule may vary depending on the severity of the condition.

Patient Information Leaflet

Patient information leaflet

Generic Name: cysteamine

Pronounced: sis-TEE-a-meen

Why do we use cysteamine?

cysteamine is used in the treatment of other conditions, including:

• Non-alcoholic fatty liver disease (NAFLD): cysteamine has been shown to reduce liver fat and improve insulin resistance in patients with NAFLD.
• Neurodegenerative disorders: cysteamine has antioxidant properties and can scavenge free radicals, which may be relevant in treating neurodegenerative disorders, such as Huntington’s disease, Parkinson’s disease, and Alzheimer’s.
• Cystic fibrosis: cysteamine can break down mucus and reduce its viscosity, which may be relevant in treating cystic fibrosis. This genetic disorder affects the respiratory and digestive systems.
• Fanconi syndrome: cysteamine has been shown to improve renal function in patients with Fanconi syndrome, a rare disorder characterized by the impaired reabsorption of certain substances in the kidney.
• Eye conditions: cysteamine eye drops are used to treat corneal cystine crystals in patients with cystinosis.