Abstract Diluted above Avogadro’s number, homeopathic medicines allegedly do not contain any molecule of their starting-materials. As Western science is historically based on the notion of matter, alternative epistemological models are needed to account for the biological actions of homeopathic high dilutions. One such model is provided by biosemiotics, an interdisciplinary field devoted to the integration of biology and semiotics based on the fundamental belief that sign production and interpretation is one of the immanent and intrinsic features of life. Several experimental studies show that the information carried by high dilutions might be evidenced by means of measurable biological effects ranging from intranuclear epigenetic phenomena to inheritable adaptive processes, and regulatory physiological and behavioral phenomena. Therefore, when the action of homeopathic medicines is considered from the semiotic point of view, they become an endless source for studies aiming not only at therapeutic applications, but also to achieve a more refined understanding of living beings and their relationships with the environment.