Walk into any behavioral health facility in America and you will encounter a peculiar arithmetic. More than three-quarters of the patients who arrive seeking help carry not one diagnosis but two: a mental health condition tangled with a substance use disorder. The clinical term is “dual diagnosis,” and it describes the overwhelming majority of people in treatment. Yet the systems built to serve them—the billing codes, the regulatory frameworks, the very architecture of care—proceed as though these intertwined conditions exist in separate universes, each requiring its own paperwork, its own specialists, its own silo.
“Our industry historically has looked at things very much in a siloed aspect,” said Neicole Knott, Vice President of Operations at NewVista Behavioral Health, which operates more than twenty facilities across Ohio and Indiana. “If somebody has a mental health issue, you’re treating mental health. If somebody has chemical dependency, you’re treating chemical dependency. The reality is that we as service providers treat them both.”
The disconnect between clinical reality and administrative structure creates friction at every level of care.
Consider a patient who arrives at an emergency room presenting with psychosis—disoriented, potentially dangerous to themselves or others. A full assessment might reveal something the initial symptoms obscured: This patient is also withdrawing from alcohol or benzodiazepines. Suddenly the treatment priority shifts entirely. Alcohol and benzodiazepine withdrawal can be fatal; the psychosis, however alarming, may resolve once the patient is medically stabilized. But no single diagnostic code captures this complexity. The paperwork demands a primary diagnosis, a clean category, when the patient in front of you defies categorization.
The Billing Divide
The financial architecture of behavioral health still reflects an era when conditions were treated in isolation. Mental health services and substance use disorder treatment often require separate billing streams, different prior authorization processes, and distinct documentation requirements—even when the same patient needs both, and even when the same clinician provides both in the same session. For intensive outpatient programs (IOP) treating dual-diagnosis patients, the constraints are particularly absurd: Providers can typically bill for only one IOP session per day, regardless of how many conditions they address.
Navigating the different coding requirements—H-codes for SUD services, a separate taxonomy of CPT codes for mental health—adds administrative burden without adding clinical value. The system demands that providers fit “round pegs into square holes,” as Knott put it, to satisfy documentation requirements that bear little relationship to the patients they actually serve.
Clinical Reality vs. Regulatory Fiction
Getting specialists to collaborate compounds the difficulty. Psychiatrists and addiction medicine physicians often train in different programs, work in different settings, and speak different clinical languages. Bridging that gap requires effort that the system neither rewards nor facilitates. “You need them all talking to each other to get the best treatment outcome,” Knott said. “And that usually is the most difficult component of care.”
Knott described the challenge of reconciling patient needs with regulatory requirements. “We have policies in place that sometimes say this patient population can’t interact with this patient population,” she said. “But the reality is, you have a person that has both. How can they not interact with themselves?”
The question of what came first—the mental illness or the addiction—persists in administrative forms long after it has ceased to matter clinically.
The Cost of Fragmentation
The siloed approach does not merely create paperwork headaches. It produces worse outcomes. Knott described seeing “chronic users of the system”—patients who cycle through acute care repeatedly, stabilized and discharged only to return weeks or months later. They are not failing treatment; treatment is failing them. “Usually it’s not because they don’t want to get well,” she said, “but because our systems don’t work well together in treating the whole patient.”
A patient might leave a facility stabilized, only to fall through the gaps that open once discharge papers are signed. Housing instability, lack of transportation to follow-up appointments, the absence of support systems—any of these can derail a recovery that seemed promising within the controlled environment of inpatient care. The acute episode gets resolved, but the underlying conditions remain undertreated, waiting to resurface.
A Path Forward?
Some models offer glimpses of what integrated care might look like. Certified Community Behavioral Health Clinics use a reimbursement structure that accounts for the actual costs of care delivery, allowing them to expand services and hire additional staff. But such arrangements remain exceptions. For most providers, the fundamental economics have not changed: Billing systems lag behind clinical evidence, and the patients who need the most integrated care receive the most fragmented treatment.
Knott urged policymakers to “truly understand the science behind behavioral health and not the opinion behind behavioral health.” The research is clear about what works. The reimbursement structure is equally clear about what it will pay for. Until those two things align, providers will continue to navigate a system that treats dual-diagnosis patients as two separate problems sharing one body rather than one person who needs care that sees them whole.
