Pharmacopsychology of Prescribing: An Introduction to the PoP Model

Internationally, there has been a significant increase in the prescribing of psychotropic medications for mood and anxiety difficulties in recent decades. However, despite this increase, the prevalence of mood disorders is also continuing to increase. This disconnect, termed the ‘treatment‐prevalence paradox’ raises questions about the effectiveness of current treatment approaches. We present the pharmacopsychology of prescribing (PoP) model, which is a conceptual framework designed to advance the understanding of factors influencing prescribing practices, treatment outcomes and long‐term effects. The PoP model comprises three core components. First, ‘input variables’, which include prescriber, patient and case‐specific characteristics that shape prescribing decisions, such as initiation, dose changes or augmentation strategies. Second, ‘medication variables’, encompassing both pharmacological and non‐pharmacological effects of psychotropic medication, such as placebo or nocebo responses, prescriber communication and unintended effects. Third, ‘treatment outcomes and downstream effects’, which capture broader implications of treatment beyond symptom change. These include secondary effects such as emotional numbing and cognitive changes, longer‐term effects such as tardive dysphoria, and psychological factors including illness beliefs, help‐seeking behaviour and subsequent clinical presentation and management. By framing the prescribing of psychotropic medication as a dynamic and multifactorial process, the PoP model integrates biological, psychological and social factors into clinical decision‐making. It provides a practical framework for clinicians to conceptualise treatment decisions, consider modifiable factors to optimise outcomes, beyond the pharmacological effects of medications, and offer a potential pathway to address the treatment‐prevalent paradox.