Overthinking and ADHD: Why Your Brain Won’t Switch Off

If you have ADHD, overthinking can feel relentless.

Your mind replays conversations, analyses decisions long after they’re made, and jumps to worst-case scenarios, often when you’re exhausted and trying to rest. Many adults with ADHD describe it as having no off switch.

This isn’t a personal failing.
It’s a reflection of how the ADHD brain processes information, emotion and uncertainty.

Let’s unpack why overthinking is so common with ADHD, and what actually helps.

What does overthinking look like with ADHD?

Overthinking with ADHD often shows up as:

• Replaying conversations and interactions on a loop

• Analysing tone, facial expressions or what might have been meant

• Difficulty letting go of mistakes or perceived missteps

• Racing thoughts at night or during downtime

• Feeling mentally “stuck” on one issue while trying to focus elsewhere

Many people assume this is anxiety, and sometimes it is, but for adults with ADHD, overthinking is often rooted in executive function and emotional regulation differences, not just worry.

Why the ADHD brain is prone to overthinking

1. A brain that doesn’t naturally “filter”

ADHD brains take in a lot of information at once. Without strong filtering, thoughts, memories, emotions and possibilities can all arrive at the same time — and stay active longer than they need to.

This makes it harder to:

• prioritise what matters

• let go of what’s finished

• mentally “close the loop”

2. Emotional intensity + delayed processing

People with ADHD often experience emotions deeply and process them after the event has passed.

That means the emotional response can keep unfolding hours or days later, fuelling rumination and replaying.

3. A history of being misunderstood

Many adults with ADHD have spent years being:

• corrected

• misunderstood

• told they were “too much” or “not enough”

Over time, the brain learns to scan interactions closely to avoid mistakes. Overthinking becomes a protective strategy, even though it’s exhausting.

4. Difficulty transitioning between mental states

ADHD can make it hard to shift gears, not just between tasks, but between thoughts.

Once a thought hooks in, the brain can struggle to disengage, especially under stress or fatigue.

Is overthinking an ADHD or anxiety thing?

It’s often both, but the difference matters.

• Anxiety-driven overthinking is usually future-focused and fear-based

• ADHD-driven overthinking is often:

  1. detail-focused

  2. replay-based

  3. triggered by emotional residue or unfinished processing

Treating ADHD-related overthinking only as anxiety can miss the underlying needs around structure, regulation and cognitive load.

Practical strategies that actually help ADHD overthinking

These aren’t about “stopping thoughts”, they’re about supporting how your brain works.

1. Externalise the thoughts

Getting thoughts out of your head reduces cognitive load.

Try:

• writing a “brain dump” before bed

• using voice notes instead of journalling

• listing worries without solving them

The goal is containment, not resolution.

2. Create a clear “end” to interactions

ADHD brains struggle with ambiguity.

After a difficult interaction, try:

• summarising what actually happened (facts only)

• naming what’s not yours to carry

• setting a time limit for reflection

This helps your brain recognise completion.

3. Reduce stimulation before rest

Overthinking often intensifies when the nervous system is already overloaded.

Support your brain by:

• lowering sensory input in the evening

• reducing scrolling before bed

• creating predictable wind-down routines

This isn’t about discipline. It’s about regulation.

4. Work with executive function, not against it

Overthinking increases when systems are unclear.

Support executive function by:

• writing things down instead of holding them mentally

• breaking decisions into smaller steps

• using visual reminders instead of mental ones

Less mental load = less rumination.

When overthinking becomes a sign you need support

If overthinking is:

• interfering with sleep

• affecting work or relationships

• contributing to burnout or emotional exhaustion

…it may be a sign that your ADHD support needs adjusting.

Coaching can help you:

• understand your thinking patterns

• build personalised strategies

• reduce shame around how your brain works

What happens when you have the right support?

Overthinking isn’t a flaw.
It’s often a sign of a brain working very hard without the right scaffolding.

With understanding, structure and neuroaffirming support, it can become quieter, not because you force it to stop, but because your brain feels safer and more supported.

ADHD and Overthinking: Common Questions

Does ADHD make you overthink?

Yes. Overthinking is very common in adults with ADHD due to differences in executive function and emotional regulation. ADHD brains often hold onto thoughts longer, making it harder to mentally “switch off” once something has happened.

Why do I replay conversations with ADHD?

Replaying conversations is common with ADHD, particularly when emotional processing happens after the interaction has ended. This delayed processing can keep thoughts looping as the brain looks for clarity or reassurance.

Is overthinking ADHD or anxiety?

Overthinking can be linked to both ADHD and anxiety. ADHD-related overthinking often involves replaying past events or getting stuck on details, while anxiety-driven overthinking tends to focus on future “what if” scenarios.

Can ADHD coaching help with overthinking?

Yes. ADHD coaching can help reduce overthinking by supporting executive function, emotional regulation and mental load. Many people find that once their brain feels better supported, rumination naturally eases.

👉 Related support

• Learn more about ADHD coaching for adults 

• Explore weekly ADHD insights  for practical strategies

• Read client experiences

• Join group coaching Unstuck:Reclaim your Rhythm ™

Until next time,

Caroline