This document discusses phytoecdysteroids, which are chemicals produced by plants as a defense against insects. These compounds mimic the ecdysteroid hormones that insects use for molting. Insects that consume phytoecdysteroids experience adverse effects like reduced weight and disrupted molting. The document outlines the chemistry and sources of phytoecdysteroids, their importance for plants and insects, potential pharmaceutical applications, and provides an example profile of the plant Leuzea carthamoides, which contains phytoecdysteroids.