Treating addiction in isolation often leads to partial recovery, as many individuals face overlapping psychiatric conditions. Dual diagnosis: addiction and co-occurring mental disorders reflects this clinical complexity. Depression, anxiety, PTSD, and bipolar disorder frequently accompany substance use, creating intricate symptom presentations and treatment challenges. Current models advocate for integrated care—where both psychiatric and substance-related symptoms are managed simultaneously through coordinated interventions. Misdiagnosis or underdiagnosis can impede progress, making comprehensive assessments critical. Evidence-based practices like integrated dual disorder treatment (IDDT) and trauma-informed therapy are reshaping therapeutic strategies. This holistic view acknowledges the interplay of biological, psychological, and environmental factors influencing both conditions.