Carcinoid Syndrome, also known as malignant carcinoid syndrome, is related to carcinoid tumors, intestinal and serotonin syndrome. An important gene associated with Carcinoid Syndrome is SDHD (Succinate Dehydrogenase Complex Subunit D), and among its related pathways/superpathways are Signal Transduction and Class A/1 (Rhodopsin-like receptors). The drugs Octreotide and Gastrointestinal Agents have been mentioned in the context of this disorder. Affiliated tissues include heart and small intestine, and related phenotypes are carcinoid tumor and night sweats