List of products in the National Drug Code with proprietary name . This medication is used to help preserve kidney function and manage kidney damage and other problems in people with an inherited disorder that causes build-up of a certain natural substance (cystine) in the body (nephropathic cystinosis). Cystine build-up can cause problems such as kidney problems, slow growth, weak bones, and eye problems. Cysteamine helps the body get rid of cystine.