Triple therapy has been used since 1996 to treat patient with HIV. OST has been used since 1995 to treat drug addicts. These treatments have deeply modified the relationship between the patient and their illness, and cause difficult with living with treatment. The nursing staff supports these patients by using specific professional practices. Theoretic models can be used to decode nursing practice. Two studies of these support practices with two different groups (patients with HIV and substituted drug addicts) shows us the most used health model—a biomedical vision in which health means no illness—and therapeutic education as instruction, in order to teach scientific knowledge to the patient. Professionals present themselves as agents, in an injunctive and prescriptive medical practice. But in the same supports, professionals use other means: they are based on individual development and its adaptation. Becoming aware of the elements of the therapeutic education relationship can modify the interaction between nursing staff and patients. Professionals could move from an agent posture to a reflexive process, allowing the patients to become more autonomous in their health attitudes.