Most people who enter addiction treatment are managing more than one thing. The substance use is visible — it’s what brought them in. But underneath it, more often than not, there’s something else: depression that’s been there for years, anxiety that made the world feel impossible to navigate without help, trauma that never got addressed, ADHD that was never diagnosed.
This isn’t a coincidence. The relationship between mental health and substance use is well-documented and bidirectional — each condition influences and often amplifies the other. Understanding that relationship, and treating both at the same time, is one of the most important things a PHP or IOP program can do.
At Green Hill Recovery, dual diagnosis treatment isn’t a specialty track or an add-on. It’s the standard.
What Is Dual Diagnosis?
Dual diagnosis — also called co-occurring disorders — refers to the presence of both a substance use disorder and at least one mental health condition in the same person at the same time. The term covers a wide range of combinations, but the most common co-occurring conditions in substance use treatment include:
- Depression and major depressive disorder
- Anxiety disorders, including generalized anxiety disorder and social anxiety
- Trauma and PTSD
- OCD and obsessive-compulsive related disorders
- Bipolar disorder
- ADHD
- Personality disorders, including borderline personality disorder and narcissistic personality disorder
These conditions are often deeply intertwined with substance use, each influencing the other in ways that compound over time. Someone may drink to find relief from anxiety or depression, experience temporary relief that reinforces the drinking, and then find that the anxiety and depression are worse than before — because alcohol’s neurological impact actively increases both over time.
Why Anxiety and Depression Often Go With Addiction
Anxiety and depression have the tendency of occurring together— and their relationship with substance use runs in both directions.
The dynamic is cyclical. Someone experiencing intense anxiety may begin pulling back from social situations, avoiding challenges at work or school, withdrawing from relationships — all as a way of managing anxiety. Over time, that withdrawal contributes to isolation, reduced engagement in meaningful activity, and the onset or worsening of depression. Depression then feeds anxiety. The cycle compounds.
Substance use enters that cycle as a solution. Something that reduces the anxiety or numbs the depression enough to get through the day.
It works in the short term — but it doesn’t interrupt the underlying cycle, and over time it adds its own layer of consequences on top of everything else.
How Green Hill Tracks Anxiety and Depression Throughout Treatment
Green Hill uses the PHQ-9 and GAD-7 — standardized, validated measures — at intake and throughout treatment to establish baselines and track whether treatment is moving the needle. If anxiety is improving but depressive symptoms are emerging, the clinical team knows early and can respond.
If neither is improving, that’s information too — it may mean the treatment approach needs to be adjusted, or that a medication evaluation is indicated. Without consistent measurement, the clinical team is working without a real picture of what’s happening, which means pivoting when something isn’t working becomes a matter of guesswork rather than data.
Can You Treat Addiction Without Treating Mental Health?
Someone who gets sober but whose depression remains untreated is still carrying the same underlying condition that made substances feel like the only reliable relief. Someone whose anxiety isn’t addressed will eventually return to whatever was managing it. The substance use was a solution to mental health issues— and until that something is treated with the same clinical seriousness, the pull toward it doesn’t go away.
Substance use doesn’t happen in isolation. People struggling with addiction are very often also managing depression, anxiety, trauma, ADHD, eating disorders, or personality disorders — and when treatment doesn’t address those underlying conditions with the same depth as the substance use itself, the likelihood of a return to use stays high. The substance was doing something. Treatment has to address what that something was.
How Green Hill Treats Dual Diagnosis in PHP and IOP
Green Hill’s approach to dual diagnosis is built into the structure of both PHP and IOP.
An Evidence-Based Curriculum for Dual Diagnosis
The group curriculum in PHP and IOP draws on therapeutic frameworks that are evidence-based for both substance use and mental health, including:
- ACT — Acceptance and Commitment Therapy — evidence-based for substance use disorders, depression, anxiety, PTSD, and OCD. Helps patients build psychological flexibility, reduce experiential avoidance, and develop values-based action that doesn’t depend on substances for relief
- DBT — Dialectical Behavior Therapy — evidence-based for emotional dysregulation, trauma, and the co-occurring conditions that most commonly accompany addiction. Provides concrete skills for distress tolerance, emotional regulation, and interpersonal effectiveness
These frameworks aren’t used separately for mental health patients and substance use patients. They’re integrated into the same curriculum because most patients presenting for substance use treatment need both.
Psychiatry and Medication Management Built Into Treatment
Getting psychiatric care requires continuity, not a fresh start. For people managing both a mental health condition and a substance use disorder, being sent to a separate provider — new intake, new records, no connection to the treatment already in progress — creates friction at a moment when continuity matters most. Fragmented care is a common reason dual diagnosis treatment breaks down.
At Green Hill, that fragmentation doesn’t exist. AIM — Green Hill’s sibling psychiatric practice — provides psychiatric evaluation and medication management within the same care network.
Psychiatric evaluation happens within the first week of treatment for patients where it’s clinically indicated. The providers doing that evaluation are a part of the Green Hill team with expertise in both psychiatry and addiction medicine — which matters because not all psychiatric providers understand the intersection of mental health and substance use at the clinical depth dual diagnosis treatment requires.
Clinical teams meet weekly. Records are shared. The psychiatry team members run a group weekly as part of the PHP and IOP programs — meaning the psychiatric piece of treatment isn’t happening in a separate office somewhere else. It’s embedded in the program itself.
Tracking Progress in Dual Diagnosis Treatment
One of the things that distinguishes Green Hill’s approach to dual diagnosis treatment is the consistency and rigor of clinical measurement throughout the course of treatment.
The BAM — Brief Addiction Monitor — tracks risk and protective factors related to substance use from intake through discharge. The PHQ-9 and GAD-7 track anxiety and depression symptoms at every clinical touchpoint. These aren’t intake-only assessments. They’re attached to ongoing appointments throughout treatment — so the clinical team always has a current picture of where someone is and whether what’s being done is working.
This matters practically. If a patient’s anxiety scores are not improving after several weeks of treatment, that’s information the team can act on — whether that means adjusting the therapeutic approach, initiating a medication evaluation, or increasing the frequency of individual therapy. If depressive symptoms emerge mid-treatment after an initial presentation that was primarily anxiety, the measurement captures that early enough to respond before it becomes a crisis.
In Green Hill’s 2025 outcomes data, 84% of patients showed measurable improvement in risk factor scores over the course of treatment. That number reflects what consistent, coordinated dual diagnosis treatment produces when it’s built into the program.
PHP vs. IOP for Dual Diagnosis: Which Is Right?
For people managing significant co-occurring mental health conditions alongside substance use, the level-of-care question carries additional clinical weight.
Partial Hospitalization Program (PHP) — five days a week — provides the clinical contact hours needed to treat both conditions at the depth and frequency they require simultaneously. For someone managing active depression or significant anxiety alongside substance use, the structure of PHP creates conditions that IOP can’t replicate. The daily contact, the consistency of clinical relationships, and the embedded psychiatric support make PHP the appropriate starting point for most dual diagnosis presentations.
Intensive Outpatient Program (IOP) — three days a week — is appropriate for people who have established enough stability to manage the days between sessions without significant clinical risk, or for people stepping down from PHP with their co-occurring conditions sufficiently stabilized.
The level-of-care recommendation at Green Hill is made using ASAM criteria — the standardized clinical framework for addiction treatment placement — and takes the full picture of both the substance use and the mental health presentation into account. The goal is to match the level of care to where someone is clinically, not to default to whatever seems most convenient.
Getting Started With Dual Diagnosis Treatment at Green Hill
If you or someone you care about is managing both substance use and a mental health condition — or if mental health symptoms are present and you’re not sure how they connect to the substance use — the place to start is a clinical assessment.
The admissions team at Green Hill works through the full picture with everyone who calls. What’s happening with the substance use, what mental health history is present, what level of care makes clinical sense, and what the process looks like from here. That conversation is confidential and doesn’t require a commitment to treatment.
Call us or schedule an assessment by clicking on the Admissions button on the top of the page and get a clear picture of what treatment could look like for your specific situation.