What a dual diagnosis is, which mental health conditions most often occur together, and how integrated treatment works.
Living with a mental health condition is hard enough on its own, and when you’re facing two or more at once, it can be difficult to know where to turn next.
This is what’s known as a dual diagnosis, or co-occurring disorders, and it’s a situation clinicians are well-versed in. With the right assessment and the right treatment plan in place, those with a dual diagnosis can be treated successfully.
This guide explains what co-occurring disorders are, along with the forms they most commonly take. We also cover the best dual diagnosis treatment approaches and how to take the first step toward feeling better again.
Quick answers
In short: A dual diagnosis, as this article uses the term, means living with two or more mental health conditions at the same time. It is also called co-occurring disorders or comorbidity. Common pairings include depression and anxiety, PTSD and depression, OCD and depression, and bipolar disorder and anxiety. Care usually aims to treat the conditions together, starting with a thorough psychiatric evaluation.
What is a dual diagnosis?
A dual diagnosis is when a person is living with two or more mental health conditions at the same time. Research shows that people who have one mental health condition are at higher risk of developing another, so it is not an unusual situation. When conditions are intertwined, treating only one can mean the others pull against any progress, which is why identifying a dual diagnosis matters.
Is a dual diagnosis the same as co-occurring disorders?
The terms overlap. Dual diagnosis, co-occurring disorders (or co-occurring conditions), and comorbidity all describe more than one condition being present together. Dual diagnosis is frequently used to mean a mental health condition alongside a substance use problem. This article uses it to describe two or more mental health conditions occurring together, such as depression and anxiety.
What are common examples of co-occurring disorders?
Common pairings include depression and anxiety, PTSD and depression, OCD and depression, and bipolar disorder and anxiety. Studies have found that 40 to 70% of people with depression also meet the criteria for at least one anxiety disorder. Neurodevelopmental conditions such as ADHD and autism also commonly occur alongside mental health conditions: around 70% of adults with ADHD have at least one other mental health condition.
What are the symptoms of a dual diagnosis?
Symptoms can overlap, and one condition can mask another. Psychological signs include persistent low mood, hopelessness, excessive worry, ongoing fear, intrusive thoughts, loss of interest, and trouble concentrating. Behavioral signs include withdrawing from family or friends, changes in sleep or appetite, avoiding certain places or situations, restlessness, and a drop in performance at work or school. None of these signs alone confirms a dual diagnosis.
How is a dual diagnosis treated?
The aim is to treat the conditions at the same time, because leaving one unaddressed can hold back progress on the other. Integrated treatment typically starts with a comprehensive psychiatric evaluation, followed by a treatment plan built around the person that may include medication management and therapy. Research links co-occurring anxiety and depression to worse outcomes, including a greater chance of recurrence and treatment resistance.
When should you get help for a dual diagnosis?
Consider talking with a mental health professional if a low mood has lasted most of the day, nearly every day, for two weeks or more, if worry or fear is getting in the way of work, school, relationships, or daily life, or if symptoms have not improved despite treatment for a single condition. If you or someone else is having thoughts of suicide or self-harm, call or text 988, or call 911 if there is immediate danger.
What Is a Dual Diagnosis?
A dual diagnosis is when a person is living with two or more mental health conditions at the same time.
Dual Diagnosis vs. Co-Occurring Disorders
You might also see it called co-occurring disorders, co-occurring conditions, or comorbidity, but in this context, they all mean more than one condition present together.
It’s also worth addressing a common source of confusion here, in that the term dual diagnosis is frequently used to describe a mental health condition alongside a substance use problem. However, in this article, we’re using it to describe when two mental health conditions occur together.
How Common Is a Dual Diagnosis, and Why Does It Happen?
Having more than one condition is far more common than many would first assume. Research shows that most people who have one mental health condition will, at some point, meet the criteria for another.1 So if you’ve been told you’re dealing with more than one condition at the same time, you’re not an unusual case.
Dual diagnoses are complex, and this is due to the many variables at play. More commonly, they interact and feed into each other, and sometimes they share an underlying cause, like genetics or difficult life experiences, which is why one can raise the likelihood of another.2
This is exactly why identifying a dual diagnosis is so important, because when two or more conditions are intertwined, treating only one part can mean the others pull against any progress being made.
Common Examples of Co-Occurring Disorders
Technically, any mental health condition can co-occur with another, but certain pairings are far more common than others.
Depression and Anxiety
Depression and anxiety are the mental health conditions most likely to be found together, according to the research. A large national survey found that 40 to 70% of people with major depression also had at least one anxiety disorder.3
If you’re living with both, it can sometimes be difficult to distinguish between the two. For example, people with depression will commonly experience nervousness and irritability, along with problems sleeping and concentrating,4 which are all similar to symptoms of anxiety.
Clinicians can record this as depression with anxious distress, which applies when at least two of the following are present on most days during a depressive episode:5
- Feeling tense
- Unusually restless
- Struggling to concentrate because of worry
- Fearing that something bad might happen
- Feeling as though you might lose control of yourself
While there are many reasons as to why this combination could occur, studies suggest that part of this reason is due to genetics. In a study of over 1,000 pairs of twins, the genetic risk for depression and generalized anxiety disorder was completely shared.6
PTSD and Depression
Post-traumatic stress disorder (PTSD) and depression are another common pairing, with research finding 42.8% of people with PTSD met the criteria for major depression.7
Some researchers believe this is partly because the two share some of the same symptoms, like losing interest in things and having trouble sleeping.7
As well as symptoms like flashbacks, if you’re experiencing both, you might notice:8
- Negative thoughts about yourself or the world around you
- Ongoing feelings of fear, anger, guilt, or shame
- Losing interest in things you used to enjoy
- Struggling to feel happiness or satisfaction
People with both conditions struggle more at work and in their social lives, and they also report higher levels of overall distress. Sadly, the risk of attempted suicide also increases, which is why seeking support for both is so important.7
OCD and Depression
For those with OCD, depression is one of the most common conditions to present alongside it. Studies show that 67.5% of people with OCD experience depression at some point in their lives.9
Many with both conditions report that their OCD started first, which suggests the depression develops as a response to the distress of living with OCD.10
If depression has set in alongside your OCD, you might notice symptoms like:10
- Low mood that lasts for weeks or months
- Finding it hard to enjoy activities you once enjoyed
- Withdrawal from friends and family
- Changes in appetite
- Changes in sleep patterns
- Feelings of hopelessness
People with OCD and depression are also more likely to overestimate the importance of intrusive thoughts and feel more responsible for having obsessions compared to non-depressed OCD patients.11 This is important as researchers found that these aspects predicted the severity of the depression,11 meaning if you’ve noticed either of these in yourself, it’s a conversation worth having with a mental health professional.
Bipolar Disorder and Anxiety
Anxiety disorders are also very common in people with bipolar disorder, with a meta-analysis finding that around 42.7% of people with bipolar disorder experience anxiety at some point.12
If you have bipolar disorder, anxiety can present at different points, including:
- During depressive episodes: You might feel tense or fear that something awful might happen.5
- During manic episodes: Feeling anxious and agitated are common.13
- Stable mood: Even when mood is stable, 34.7% of people with bipolar disorder meet the criteria for an anxiety disorder.14
The presence of anxiety can make bipolar disorder harder to manage without professional support, and has been linked to earlier onset and more frequent mood episodes.12 This makes it very important for recovery to identify a dual diagnosis of bipolar and anxiety.
Neurodevelopmental Conditions and Mental Health Conditions
First, it’s important to understand that neurodevelopmental conditions like ADHD and autism are not mental health conditions. They aren’t something to be “cured,” rather, something to be managed. That said, they very commonly occur alongside mental health conditions.
Around 70% of adults with ADHD have at least one other mental health condition, with anxiety affecting up to half and depression affecting a large share too.15
Autistic adults show similar results, with research finding that around 42% experience an anxiety disorder and 37% experience depression at some point.16
The reasons behind why this happens are complex, but it’s partly because living with a neurodevelopmental condition in a world built for neurotypical people can be a real source of stress.
There’s also the risk that a treatable mental health condition gets missed entirely, with signs attributed to the symptoms of ADHD or autism.17
What Are the Symptoms and Signs of a Dual Diagnosis?
If you’re reading this because you’re worried about yourself or someone you love, one of the hardest challenges is simply making sense of what you’re seeing.
Identifying a dual diagnosis can be difficult early on. When two mental health conditions occur together, such as depression alongside severe anxiety or PTSD with an eating disorder, their symptoms frequently overlap and one condition can easily mask another. It is very common for a person’s distress to be attributed to a single primary diagnosis, while a co-occurring second condition goes completely unnoticed.
Knowing what to look for gives you the best chance of recognizing when multiple conditions are interacting underneath the surface.
Psychological Symptoms (Internal Signs)
If you are evaluating your own mental health, pay attention to persistent emotional and cognitive patterns, such as:
- Persistent low mood: Ongoing feelings of emptiness, sadness, or hopelessness
- High anxiety: Excessive, uncontrollable worry or constant, severe fear
- Loss of interest: No longer finding joy in hobbies, activities, or relationships you once valued
- Cognitive strain: Intrusive thoughts, difficulty concentrating, or trouble making everyday decisions
Behavioral Symptoms (External Signs)
When you are worried about a loved one, internal emotional experiences can be hard to spot. Focus instead on noticeable behavioral shifts that often develop as coping mechanisms or responses to internal distress:
- Social withdrawal: Pulling away from family, friends, and usual support networks
- Routine changes: Sudden changes in sleep patterns, appetite, or personal care
- Avoidance: Going out of the way to dodge specific places, people, or triggering situations
- Compulsive habits: Marked restlessness, agitation, or repeatedly performing specific actions and routines
- Decline in functioning: A distinct drop in performance at school or work or with daily responsibilities
When Symptoms Start Affecting Daily Life
Of all these signs, clinicians pay close attention to how much they’re affecting daily life. If someone is struggling with everyday tasks, like washing or eating, it’s a sign that support should be considered. The same goes for falling behind at work or school, or being placed on a performance plan at work.
None of these signs alone confirms a mental health condition or a dual diagnosis. But when several appear together, or they start getting in the way of daily life, it’s a good reason to turn to professional help.
Trusting your instinct and seeking a proper assessment can be the first step toward getting the treatment you or a loved one truly need.
Why a Dual Diagnosis Needs Specialized Treatment
When a person has a dual diagnosis, the aim is to treat both of the conditions at the same time. The conditions within the dual diagnosis can feed each other, so leaving one unaddressed while focusing on the other can hold back progress.
Research supports this and finds that when anxiety and depression occur together, they’re linked to worse outcomes, including a greater chance of recurrence and treatment resistance.18 Someone could make headway on their depression, only to find that untreated anxiety keeps pulling them back.
This is exactly why integrated treatment for co-occurring disorders matters, because rather than treating one condition in isolation, care focuses on how a person’s conditions interact. The result is treatment that is tailored to the person’s specific needs, rather than a single diagnosis.
It’s also why working with a mental health specialist makes such a difference, especially when medication is involved. Psychiatric providers understand how different medications interact, and that means they can combine them so each one works as well as possible, without making a co-occurring condition worse.
What Does Integrated Treatment for Co-Occurring Disorders Look Like?
Integrated treatment can take place in either an inpatient or outpatient setting depending on the needs of the person. Inpatient means treatment is received in a hospital or residential setting, with outpatient being the more flexible option that allows you to return home every day after treatment has finished for that day.
There’s no better option here, and, as stated, the setting is based on the person’s current needs.
Regardless of the setting, there are similar stages to how the process of receiving mental health treatment works, which we explore below.
A Comprehensive Assessment
The first step starts with a psychiatric evaluation to fully understand you, your background, your previous mental health history, and how you’re currently feeling. It’s a relaxed conversation, necessary so that the clinicians can build a better idea of what you’re going through and make sure nothing is missed.
Because co-occurring conditions overlap, this sometimes takes more than one appointment to get right, which is a good thing, as an accurate diagnosis is what good care is built on.
An Integrated Treatment Plan
Once a clear picture has been formed, the next step is to turn this information into a plan that addresses the conditions identified. This plan is built around you, with your needs in mind, and adjusted as things change over time. This ensures the care keeps pace with where you are.
Medication Management
In some cases, medication will be a part of the integrated plan. Medication management means working with a psychiatric provider to monitor how the medication is working and make careful adjustments if need be.
When more than one condition is involved, this is done carefully, as certain situations require different approaches. For example, for someone with bipolar disorder, mood needs to be stabilized first before other medications are added.
Therapy
Therapy is an important part of the treatment process, and there are many different types of therapies that can help with certain conditions.
For example, if a person is dealing with both depression and anxiety together, cognitive behavioral therapy (CBT) may be considered. This is because CBT can help to treat several conditions at once by targeting the similarities the conditions share.19
Another example might be trauma-focused therapies for those dealing with PTSD and depression. Trauma-focused therapies, like cognitive processing therapy (CPT), are treated as the gold standard, and treating the associated trauma can help ease the co-occurring depression at the same time.20
ADHD deserves a special mention here, because it works a little differently from two or more mental health conditions co-occurring. ADHD isn’t something to be cured, but it is very much managed through a mix of medication and practical support like coaching or building coping strategies. Getting the right support for ADHD can ease the overwhelm that feeds conditions like anxiety, meaning the two can improve together.
When Should You Reach Out for Help?
It isn’t always easy to know when the right time is to seek support, and that’s true whether you’re thinking about yourself or a loved one. Instead, it’s worth taking the time to honestly answer a set of questions that may indicate it’s the right time to reach out for help:
- Has a low mood lasted most of the day, nearly every day, for two weeks or more?
- Is worry or fear getting in the way of work, school, relationships, or daily life?
- Have symptoms failed to improve despite receiving treatment for a single condition?
- Does it feel like whenever you make progress in one area, you’re held back by another?
Answering “yes” to one or more of these questions doesn’t automatically diagnose you with something, but it does indicate that a conversation with a mental health professional could benefit you.
Some situations need urgent help rather than a planned appointment, such as when you or someone else is:
- Having thoughts of suicide or self-harm
- A danger to themselves or others
- Losing touch with reality
These are key indicators to treat the situation as an emergency. In the US, you can call or text the 988 Suicide and Crisis Lifeline at any time. If you or the other person is in immediate danger, call 911 or go to the nearest emergency room.
How Peak Mental Healthcare Can Help
Getting the right diagnosis can be one of the most difficult parts of getting treatment for a dual diagnosis, and this is where Peak Mental Healthcare can help.
We’re an outpatient psychiatric practice with locations across Arizona and Colorado. We’re able to help you understand what’s going on and help lay the foundations of your treatment in place.
We begin with a thorough psychiatric evaluation to understand your situation and use this information to build a personalized treatment plan. We’re also able to help you with medication management, adjusting as we move forward and providing support for you in between appointments.
We also work alongside therapists so that the medical and the talking-therapy sides of your treatment are well informed and support one another.
If you feel as though you, or a loved one, may be dealing with a mental health condition, it’s important to act now and book your first evaluation with us. Booking an evaluation with Peak is a simple and low-pressure first step, with same-day appointments frequently available.
If you’d like to learn more about the services we offer, or more information in general, contact your nearest Peak office. A member of our team will be more than happy to answer any questions you may have.
Ready to schedule an appointment?
Contact Peak Mental Healthcare today to book your first appointment. We’re here to help you take the next step toward feeling like yourself again.
This article is for general education and isn't a substitute for personal medical advice.
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