When someone struggles with both a mental health issue and a substance use problem, it can feel like fighting a battle on two fronts. These overlapping challenges are known as concurrent disorders or dual diagnosis. And they’re more common than many people realize.
But why do mental illness and addiction so often go hand in hand? And what’s actually going on in the brain when both are present?
Let’s take a closer look—through the lens of psychotherapy, brain science, and human experience.
How Do Mental Illness and Addiction Affect the Brain?
Our brains are wired to keep us in balance. Mood, motivation, sleep, appetite, energy, and decision-making are all regulated by chemical messengers called neurotransmitters—like dopamine, serotonin, and norepinephrine.
When someone is living with a mental illness such as depression, anxiety, bipolar disorder, or PTSD, this balance is often disrupted. For example, people with depression may have lower levels of serotonin or struggle to feel pleasure because dopamine signalling is weakened.
Substances like alcohol, cannabis, or stimulants can temporarily change those brain chemicals.
This might bring relief—at least at first.
Self-Medication: When Addiction Starts as a Coping Strategy
One reason people turn to substances is to cope with emotional pain. Someone with anxiety might drink to calm their nerves. Meanwhile, someone with PTSD might use cannabis to numb flashbacks.
Someone with depression might take stimulants to feel something—anything.
This is called self-medication. In the short term, it may feel helpful. But over time, it often makes things worse.
Here’s why: substances hijack the brain’s reward system. They flood the brain with feel-good chemicals, which can lead to tolerance (needing more to get the same effect), dependence, and eventually addiction. At the same time, the underlying mental health condition remains untreated, or gets worse.
How Do Mental Health and Addiction Feed Each Other?
Mental health challenges and substance use often reinforce each other in a harmful loop that’s difficult to break without integrated support.
It becomes a cycle:
- The person uses a substance to manage mental health symptoms.
- The substance worsens the mental health symptoms over time.
- The person uses more of the substance to try and cope. This cycle makes both conditions harder to treat, and the person can feel stuck, ashamed, or hopeless.
Integrated treatment means:
- One team of professionals supports both issues.
- Therapy is focused on both mental health and substance use, not one or the other.
- The person is seen as a whole—not as a diagnosis or a label.
Hope and Healing with Concurrent Disorders
Living with a concurrent disorder can feel overwhelming. But with the right support, healing is absolutely possible.
Recovery doesn’t mean being “perfect.” It means understanding your triggers, finding healthier ways to cope, and reconnecting with your values and goals. It means learning that you’re not broken—you’re human.
If you or someone you love is struggling with both mental health and substance use, know this: you are not alone, and you deserve care that sees all of you.
The brain is powerful—and so is the human spirit. Even when the road is hard, healing can happen. If you’re living with a concurrent disorder, you’re not fighting two battles alone. Our team of therapists at Rebound Total Health are here to help you with concurrent disorders. We lead with compassion, and that’s a powerful place to begin.
Book a consultation and start your journey to better mental health today!
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