Adherence to medication interventions is a critical factor in achieving desired health outcomes and reducing healthcare costs, particularly among discharged patients. However, discharged patients usually exhibit high non-adherence rates. Motivated by exploring the potential unintended consequences of online health platforms, when patients distrust their attending doctors, this study aims to identify and formulate the factors influencing discharged patients' medication adherence. We conducted a sequential analysis. Phase I involved an exploratory investigation through in-depth semi-structured interviews with ten discharged patients. Inspired by Phase I findings, Phase II empirically validate a theoretical model using an online survey with 309 participants. Results showed that patients' distrust in doctors' competence emerged as crucial in harming medication adherence. Meanwhile, the study uncovered the potential pitfalls of online health platforms with professionals’ assistance in patients' medication behaviors. The study also revealed the complex online-offline dilemmas from hospitalization to self-management phases faced by discharged patients. This study contributes to the existing literature by uncovering potential challenges in online platforms when the complex online-offline dilemma exists. Practically, this study can benefit related stakeholders to pay attention to the potential conflicts and explore opportunities to integrate online medical services and traditional clinical systems.