Cysteamine is a radiation-protective agent that oxidizes in air to form cystamine. It can be given intravenously or orally to treat radiation sickness. The bitartrate and hydrochloride salt forms are indicated for the treatment of neuropathic cystinosis in patients 6 years old and older. [PubChem]. Cysteamine is marketed under several brand names such as Cystaran™, Procysbi, and Cystagon®.
Humans and other mammals
Given intravenously or orally to treat radiation sickness. The bitartrate salts (Cystagon® and Procysbi) have been used for the oral treatment of nephropathic cystinosis and cystinurea. The hydrochloride salt (Cystaran™) is indicated for the treatment of corneal cystine crystal accumulation in cystinosis patients.
People born without the ability to metabolize the amino acid cystine suffer from cystinosis, a rare inherited disorder characterized by the deposition and accumulation of cystine crystals throughout the body. These crystals cause considerable damage, particularly in the kidney and eye. Kidney failure can occur by the age of 10 in untreated patients. Cysteamine prevents the accumulation of cystine crystals and is prescribed to prevent further kidney and eye damage. Cysteamine helps to convert cystine into less harmful chemical forms that can be removed from cells.
Mechanism of action
The free thiol cysteamine depletes cystinotic leukocytes and other cells of cystine, whose accumulation is considered the cause of organ damage in cystinosis. Cysteamine cleaves the disulfide bond with cystine to produce molecules that can escape the metabolic defect in cystinosis and cystinuria.
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison
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