ADHD, anxiety and depression: untangling the overlap

ADHD rarely arrives alone. Around two-thirds of adults with ADHD have at least one co-occurring condition, and anxiety and depression are among the most common. Because the symptoms overlap, it’s easy for one condition to be treated while another is missed — which is why a good assessment screens for all of them.

Why they overlap

There are two things going on. First, ADHD and mood or anxiety conditions genuinely co-occur more often than chance. Second, living with undiagnosed ADHD — years of underachieving, missed deadlines, and self-blame — is itself a powerful driver of anxiety and low mood. Sometimes the anxiety and depression are secondary to the ADHD that was never recognised.

Where the symptoms blur

Several experiences can point to more than one condition:

• Difficulty concentrating can come from ADHD, anxiety, or depression
• Restlessness and racing thoughts overlap between ADHD and anxiety
• Low motivation and difficulty starting tasks can look like depression or ADHD
• Sleep problems are common to all three
• Emotional intensity features in ADHD and in mood conditions

Because of this overlap, someone can be treated for anxiety or depression for years with only partial improvement — because the ADHD underneath is still unaddressed.

Why the distinction matters

Getting the full picture matters because the treatments differ. Treating depression won’t resolve ADHD-driven difficulties, and treating ADHD alone may not be enough if there’s significant anxiety or low mood alongside it. A thorough assessment looks at the whole picture, considers timelines (what came first, and when), and screens for co-occurring conditions rather than stopping at the first label that fits.

What good assessment looks like

A specialist assessment for ADHD should:

• Review current symptoms and their history since childhood
• Consider how difficulties affect different areas of life
• Screen for co-occurring conditions such as anxiety, depression and sleep problems
• Result in a clear written report and a plan that addresses the whole picture

Getting the right help

If you’ve been treated for anxiety or depression but still feel like something hasn’t been fully explained, it may be worth considering ADHD. Our free 60-second test is a first step, and a specialist assessment through NHS Right to Choose can look at everything together — without a years-long wait.

This article is general information and not a substitute for professional medical advice. If you’re struggling with your mental health, please speak to your GP — or in a crisis, call 999 or NHS 111, or Samaritans free on 116 123.