ADHD, anxiety and depression in adults

Written and professionally reviewed by Felix Enghoff Klich, authorised psychologist, and Martin Bergholtz, doctor in specialist training in psychiatry
Last updated: October 2026

Many adults with ADHD have a long history behind them before they get the diagnosis. Often they first sought help for anxiety, stress or depression. The treatment may have helped a little, but the concentration difficulties, the restlessness and the chaos in everyday life have persisted. Only when someone looks at the whole picture does it make sense.

ADHD, anxiety and depression very often occur together, and the symptoms can be strikingly similar. In this article you can read how they are connected, how to tell them apart, and why a broad assessment makes a big difference to getting the right treatment.

How often do adults with ADHD also have anxiety or depression?

The vast majority of adults with ADHD also struggle with something else. In a large American population survey, 47% of adults with ADHD had had an anxiety disorder, and 38% depression or another mood disorder, within the past year. By comparison, the figures are far lower in the rest of the population.

The connection also goes the other way: among adults being treated for anxiety or depression, some have ADHD that has never been detected.

Why are ADHD, anxiety and depression connected?

There are several explanations, and they often work together:

• Many years of headwind: Struggling with forgetfulness, procrastination and disorganisation leads to setbacks at school, at work and in relationships. Over time this can wear down self-esteem and lead to low mood.
• Constant stress: Many people with ADHD live with a feeling of being behind. Worrying about forgetting something important or not measuring up can develop into actual anxiety.
• Overcompensation: Some hold everyday life together with lists, control and extra hours. It works for a while, but costs energy and can end in stress and burnout.
• Emotional vulnerability: ADHD often affects the ability to regulate emotions. Disappointments and criticism can hit harder and linger longer in the body.
• Shared vulnerability: Heredity and the brain's regulation of attention and mood play a role in all three conditions.

Symptoms that look alike

It is not surprising that the conditions are confused. Several of the most common symptoms recur:

• Concentration difficulties: seen in ADHD, anxiety and depression
• Inner restlessness and agitation: seen especially in ADHD and anxiety
• Sleep problems: seen in all three
• Irritability and a short fuse: seen in all three
• Lack of energy and initiative: seen in ADHD and depression
• Forgetfulness and difficulty getting things done: seen in ADHD and depression

That is why it is not enough to look at the symptoms as they are right now. What matters is when they arose and how they have developed.

How to tell the difference

ADHD

ADHD is a developmental disorder that has been present since childhood. The difficulties with attention, impulsivity and structure are present in good and bad periods and in many contexts, at home, at work and in leisure time. Read more about ADHD symptoms in adults.

Depression

Depression typically comes in periods that differ clearly from how you usually feel. The characteristics are low mood, reduced interest and pleasure and reduced energy for at least two weeks. The concentration difficulties arise with the depression and ease when it passes. Read about depression and treatment.

Anxiety

In anxiety, the restlessness is driven by worries, fear or bodily alarm, and people often start avoiding situations. Concentration fails because thoughts revolve around what you fear. In ADHD, the restlessness is more constant and not linked to particular worries. Read about anxiety and treatment.

Many people have both ADHD and anxiety or depression at the same time. Then it is not about either-or, but about understanding what is what, and what should be treated first.

Signs that ADHD may be behind it

Consider whether ADHD may be part of the explanation if you recognise several of these:

• You have had difficulty with concentration, structure or restlessness for as long as you can remember, also before the anxiety or depression.
• Treatment for anxiety or depression has helped your mood, but not forgetfulness, procrastination and chaos.
• You have been told that you are lazy, sloppy or not trying hard enough, even though you struggle more than most.
• Your worries are often about forgetting things, being late or not getting done what you need to.
• You act impulsively, e.g. with money, words or decisions, and regret it afterwards.
• There is ADHD in your family.

You can get a first indication with the ASRS self-test for ADHD. A test cannot provide a diagnosis, but it can be a good starting point for a conversation.

Why a broad assessment is important

If you only look at one diagnosis at a time, you risk overlooking something. Untreated ADHD can maintain depression or anxiety, and severe depression can make it look like ADHD, even when it is not.

At Nordisk Psykiatri, every assessment starts with a broad clinical consultation and screening, where we also look for anxiety, depression and other mental health conditions. We go through your development from childhood onwards, and the psychologist and doctor assess the overall picture together. Read how an ADHD assessment works with us, or about psychiatric assessment in general.

If you are currently in a severe depression, it may be necessary to treat it first. Severe depressive symptoms can affect concentration and memory so much that an ADHD assessment becomes uncertain. We assess this together with you.

Treatment when you have more than one diagnosis

When ADHD, anxiety and depression occur together, we make an overall plan. Typically, what causes the most strain is treated first, and then we look at what remains. Treatment may consist of:

• Psychoeducation: knowledge about ADHD and how it interacts with anxiety and low mood. For many, the understanding itself is a relief.
• Psychotherapy: e.g. cognitive behavioural therapy adapted to ADHD, working with everyday strategies, worries and self-criticism.
• Medical treatment: ADHD medication can ease concentration and structure, and for some, anxiety and low mood lessen when everyday life becomes more manageable. With depression or anxiety, other medication may also be needed. This is assessed individually by a doctor.

Read more about medical treatment of ADHD and about the difference between a psychologist and a psychiatrist.

Help at Nordisk Psykiatri

At Nordisk Psykiatri, psychologist and doctor work together on both assessment and treatment. You can come without a referral, and an assessment can typically be completed within 4 weeks. See prices, or contact us for an initial consultation.

Frequently asked questions

Can depression look like ADHD?

Yes. Both can cause concentration difficulties, lack of energy and difficulty getting things done. The main difference is that ADHD has been present since childhood and is there in all periods, while depression typically comes in episodes.

Can ADHD cause anxiety?

ADHD does not cause anxiety directly, but many years of stress, setbacks and worry about forgetting or not measuring up can develop into an anxiety disorder. In large studies, almost one in two adults with ADHD also has an anxiety disorder.

Can you be assessed for ADHD if you have anxiety or depression?

Yes. A thorough assessment takes other conditions into account. With severe depression, however, it may be best to treat it first, so that the ADHD assessment is as reliable as possible.

Does ADHD medication help with anxiety and depression?

ADHD medication does not treat anxiety or depression directly. But when concentration and overview improve, some find that worries and low mood take up less space. For others, ADHD medication can increase restlessness at first, which is why the treatment is closely monitored.

Does antidepressant medication help with ADHD?

Standard antidepressant medication does not, as a rule, treat the core symptoms of ADHD, such as concentration difficulties and impulsivity. If you have both, each condition may need treatment.

What should be treated first?

It depends on what causes the most strain. Often severe depression or anxiety is treated first, after which ADHD is assessed and treated. The plan is always made individually.

Sources

• Kessler, R. C. et al. (2006). The prevalence and correlates of adult ADHD in the United States: results from the National Comorbidity Survey Replication. American Journal of Psychiatry, 163(4), 716–723.
• Katzman, M. A. et al. (2017). Adult ADHD and comorbid disorders: clinical implications of a dimensional approach. BMC Psychiatry, 17, 302.
• National Institute for Health and Care Excellence (2018). Attention deficit hyperactivity disorder: diagnosis and management (NG87).
• Danish Health Authority (Sundhedsstyrelsen). National clinical guideline for the assessment and treatment of ADHD in adults. sst.dk