Final answer:
The social worker should initially address the client's possible PTSD symptoms since they could be exacerbating his other issues including substance use, productivity at work, and personal losses.
Step-by-step explanation:
The 45-year-old male client, a veteran of the Iraq war, presents a complex situation involving substance use, potential mental health issues, and serious personal and financial difficulties. Given the multifaceted nature of the client's issues and the immediate concerns raised, the social worker should initially focus on Possible PTSD symptoms associated with military deployment. The symptoms of PTSD, including the client's use of prescription opiates despite a lack of physical pain, may be contributing to his decreased productivity and mistakes at work, and addressing these underlying psychological issues is critical for long-term recovery and improvement in other areas of his life. While his grief, housing issues, and drug use are also pressing concerns, treating possible PTSD symptoms could be imperative since it may be an underlying factor exacerbating his other difficulties.