1. failure of a disease or disorder to respond positively or significantly to treatment, as in treatment-resistant depression.

2. reluctance on the part of an individual to accept psychological or medical treatment or to comply with the therapist’s or physician’s prescribed regimens. In psychotherapy, treatment resistance is the lack of a positive response by a client to the techniques being used and results in a rupture in the therapeutic alliance, which requires the use of other strategies by the therapist to repair the alliance. Examples of treatment resistance are noncompliance with assignments, extended silences, talking about tangential issues, and seemingly pointless debates about the therapist’s approach, suggestions, and interpretations. See also nonadherence.