Glucagon is a hormone produced and secreted by the alpha cells in the Islets of Langerhans within the pancreas. It plays a critical role in regulating blood sugar (glucose) levels in the body and acts in opposition to the hormone insulin. Glucagon is administered by injection to counteract diabetic hypoglycaemia.

Unit 3,

Reference: Oxford Concise Colour Medical Dictionary (7th Edition, Kindle Edition) Oxford University Press 2020 ISBN-13: 978-0198836629, p1551