Types of Medication Non-adherence & Approaches to Enhance Medication Adherence in Mental Health Disorders: A Narrative Review

Background: Medication non-adherence (MNA) presents a significant obstacle that negatively impacts treatment effectiveness in mental health disorders. The objective of this review is to study different types of MNA and interventions designed to enhance medication adherence among individuals with mental health disorders. Methods: We conducted an electronic search on PubMed and Google Scholar using keywords such as adherence, non-adherence, compliance, non-compliance, mental health disorders, psychotropic drugs, major depressive disorder (MDD), schizophrenia, anxiety disorders, and bipolar disorders (BD). From the search results, we selected studies pertinent to the objective of the review. Results: Non-adherence can be categorized into primary nonadherence (not starting medication) and secondary non-adherence (not taking the medication as directed). Generally, we can group the reasons for non-adherence into unintentional and intentional. Unintentional non-adherence (UNA) arises when patients genuinely desire to comply with their prescribed course of therapy but are hindered by factors beyond their control. When addressing UNA, interventions should simplify medication regimens, utilize long-acting injectable (LAIs) medications, offer tools to manage medication and provide follow-up reminders. When a patient deliberately decides not to follow their treatment plan, this is known as intentional non-adherence. To improve intentional non-adherence, the focus should be on patient-centred care and shared decision-making, psychoeducation, effective doctor-patient communication, cognitive-behavioral strategies, and addressing concerns related to the side effects of psychotropic drugs. Conclusion: It is crucial to understand that there is no universal solution to address non-adherence in mental health disorders. Each patient has distinct needs and characteristics, making personalized strategies and interventions of utmost significance.