This contribution intends to show how philosophy of science and medicine have been increasingly interacting and are further called to interact in elaborating different models, in clarifying notions like explanation, mechanism and generalization in the medical context, and in tackling the relations between explaining and intervening. On these and related topics conceptual and methodological investigations on diseases and medical research and practice are both asking for philosophical reflections and questioning available philosophical notions. In what follows, I shall illustrate how philosophy of science and medicine are mutually helping and challenging each other referring to specific medical fields that have only recently become a focus for philosophy of science, such as epidemiology, psychiatry and psychiatric epidemiology.