Tetradecapeptides

Linaclotide (sold under the brand name Linzess in the US and Mexico, and as Constella elsewhere) is a drug used to treat irritable bowel syndrome with constipation and chronic constipation with no known cause. It has a black box warning about the risk of serious dehydration in children in the US; the most common adverse effects in others include diarrhea.

Kisspeptins (including kisspeptin-54 (KP-54), formerly known as metastin) are proteins encoded by the KISS1 gene in humans. Kisspeptins are ligands of the G-protein coupled receptor, GPR54. Kiss1 was originally identified as a human metastasis suppressor gene that has the ability to suppress melanoma and breast cancer metastasis. Kisspeptin-GPR54 signaling has an important role in initiating secretion of gonadotropin-releasing hormone (GnRH) at puberty, the extent of which is an area of ongoing research. Gonadotropin-releasing hormone is released from the hypothalamus to act on the anterior pi