This review presents the main patterns of synthesis for theranostics platforms. We examine various approaches to the interpretation of theranostics, statistics of publications drawn from the PubMed database, and the solid-state and medicinal chemistry methods used for the formation of nanotheranostic objects. We highlight and analyze chemical methods for the modification of nanoparticles, synthesis of spacers with functional end-groups, and the immobilization of medicinal substances and fluorophores. An overview of the modern solutions applied in various fields of medicine is provided, along with an outline of specific examples and an analysis of modern trends and development areas of theranostics as a part of personalized medicine.