[Appropriate use of medicines in patients with rheumatoid arthritis, osteoarthritis and osteoporosis--pharmacists' role].

The care of patients with osteoarthritis, rheumatoid arthritis and osteoporosis often requires a pharmacologic approach. The co-prescription of several medicines is regularly needed in order to optimise treatment. Several recent studies, however, have identified instances of inappropriate medicines use in these patients. This mainly includes "misuse" (inappropriate medicines use in terms of dosing, choice of drug, treatment modalities, treatment duration, interactions,...) and "underuse" (omission of drug therapy that is indicated for the treatment or prevention of a disease or condition). The following examples are discussed: insufficient or inappropriate pain control, use of codeine and tramadol in CYPD2D6 poor metabolisers, underuse or delayed use of disease-modifying anti-rheumatic drugs, medication errors with methotrexate, underuse of medicines for the treatment of osteoporosis. By being aware of these events of inappropriate medicines use, the pharmacist should be better able to deliver pharmaceutical care to these patients. The aim is to improve patients' quality of life.