Reconceptualizing Side Effects in Psychotherapy: from Medical Effects to Interactive Therapeutic Proposals

The medical model provides the dominant framework for psychotherapy practice, with informed consent procedures directly adapted from medical treatment protocols. This paper critically examines the validity of this framework, particularly regarding the conceptualization and disclosure of treatment side effects. While acknowledging the spectrum of directiveness across psychotherapeutic approaches, we argue that the medical metaphor fundamentally misrepresents psychotherapy, where most interventions function as proposals rather than direct actions upon patients. This claim is supported by empirical findings demonstrating that patient engagement predicts outcome variance, weak associations between specific interventions and outcomes (including dismantling studies, protocol adherence research, and direct treatment comparisons), and the inconsistency of classifying certain therapy outcomes as side effects when similar changes from medical treatments or life experiences require no formal disclosure. Unlike medical procedures, where patient autonomy ends after consenting to treatment, psychotherapeutic interventions continuously interact with patient agency. Treating therapeutic interventions as proposals rather than direct effects better aligns with empirical findings and carries significant implications for informed consent. Current requirements may create an unbalanced comparison between psychotherapy and psychiatric pharmacological treatments by requiring disclosure of “side effects” in psychotherapy that are not disclosed in medical treatments, despite psychotherapy’s safer profile. This practice may undermine psychotherapy’s goal of fostering patient autonomy and compromise informed treatment decisions.