Objectives: This study investigated medication perceptions, adherence patterns, self-discontinuation experiences, and information sources among psychiatric outpatients to provide evidence for improving adherence strategies. Methods: A cross-sectional survey was conducted with 79 outpatients from a University Hospital, Department of Psychiatry. Self-administered questionnaires assessed diagnostic awareness, medication perceptions, adherence behaviors, discontinuation experiences, side effects, and information sources. Results: Overall, 89.7% knew their psychiatric diagnosis and 88.2% perceived medication as effective. While 73.1% rarely forgot medication, 35.9% had previously self-discontinued treatment. Medication adherence was significantly associated with previous discontinuation experience (p=0.006), whereas diagnostic awareness and efficacy perception were not. Primary discontinuation reasons were symptom improvement (53.6%) and physical discomfort (35.7%). Common side effects included weight gain (n=31), daytime drowsiness (n=26), memory impairment (n=24), and concentration problems (n=22). Patients primarily obtained side effect information from TV/internet (27.8%) rather than healthcare providers (20.3%). Most patients desired additional information about side effects (57.0%) and medication effects (54.4%). Conclusion Daily medication-taking behaviors were more predictive of treatment discontinuation than cognitive factors in this outpatient sample. Discontinuation due to symptom improvement and reliance on non-medical information sources highlights the need for enhanced patient education regarding relapse risks and systematic provision of accurate medication information.