I'm thinking entropy, which, in thermodynamics, is a measure if natural tendancy of systems to slide from order towards disorder. Not sure whether this can be applied to living systems. Disordered & unregulated may also be antonyms of homeostasis. read more
Homeostasis: the tendency towards a relatively stable equilibrium between interdependent elements of the human body. Relevance ranks synonyms and suggests the best matches based on how closely a synonym’s sense matches the sense you selected. read more