Defining a nonpaternalistic yet achievable form of trust in medicine in an era of simultaneous patient empowerment and institutional control has been and remains an important task of bioethics. The 'crisis of trust' in medicine has been viewed mainly as the problem of getting patients to trust their health care providers, especially physicians. However, since paradigmatic cases of trust are mutual, bioethicists must pay more attention to physician trust in patients. A physician's view of the reasonableness of trust in a particular patient is affected not just by his or her relationship with that patient, but also by what is going on institutionally, professionally, legally and politically with regard to a given treatment or intervention. Since general moral principles are insufficient in determining the moral value and reasonableness of trust in particular instances, I discuss in detail the role of trust and distrust in the specific case of treating patients with medications implicated in drug abuse. I conclude that it is important to become aware, first, of the clinical significance of physician trust and distrust in patients, and second, of the many factors which inform both of these moral attitudes. These two claims together suggest that a central, but overlooked, virtue of medical practice is reflective, context-responsive trust in patients.