The aim of this qualitative study was to explore patients' representations regarding generics in patients suffering from non-specific disabling chronic musculoskeletal pain, as these patients are confronted with the issue of the prescription and/or substitution of original formulations with generics. Patients' representations suggest that they might be confident in taking a generic medication: when the generic medication is prescribed by the physician and each prescription is discussed, i.e., the patient is prescribed the generic version of a given medication and not a generic medication. Economic arguments are not sufficient to accept substitution. Negative representations require attention and need be considered.