Radiopharmaceuticals are increasingly playing a leading role in diagnosing,
monitoring, and treating disease. In comparison with conventional pharmaceuticals, the
development of radiopharmaceuticals does follow the principles of medicinal chemistry
in the context of imaging-altered physiological processes. The design of a novel radiopharmaceutical has several steps similar to conventional drug discovery and some particularity. In the present work, we revisited the insights of medicinal chemistry in the current
radiopharmaceutical development giving examples in oncology, neurology, and cardiology. In this regard, we overviewed the literature on radiopharmaceutical development to
study overexpressed targets such as prostate-specific membrane antigen and fibroblast activation protein in cancer; β-amyloid plaques and tau protein in brain disorders; and angiotensin II type 1 receptor in cardiac disease. The work addresses concepts in the field
of radiopharmacy with a special focus on the potential use of radiopharmaceuticals for
nuclear imaging and theranostics.