What is ADHD? Symptoms of ADHD in adults and children

Student wearing headphones with peaceful, focused expression during ambient soundscape study session for concentration

Attention Deficit Hyperactivity Disorder is a neurodevelopmental condition that can impact daily functioning, learning, relationships, and emotional wellbeing. This guide explains what ADHD is, what it feels like, and the common symptoms in both adults and children.

Living with ADHD can feel like being constantly hungry for stimulation.

What is ADHD?

ADHD is a lifelong neurodevelopmental condition involving difficulties with attention and/or predominantly hyperactive traits and/or predominantly impulsive features.

To make a diagnosis, clinicians require that several inattentive or hyperactive-impulsive symptoms:

Were present before age 12
Exist in two or more settings (e.g., home, work/school, social situations)
Persist for at least six months

Therapist and client engaged in a counseling session in a warm, naturally-lit therapy room with comfortable seating and calming décor.

ADHD symptoms in adults

Feeling like your brain can't sit still can be exhausting. It can disrupt sleep, make work harder, and strain relationships. Many adults also feel misunderstood or judged, even when they're trying their best to fit in.

Common signs of inattention in adults include:

Being easily distracted
Forgetting what you planned to do that day
Frequently losing your keys or phone
Leaving tasks unfinished
Struggling to follow instructions

Common signs of hyperactivity or impulsivity in adults include:

Feeling restless
Making quick decisions without thinking
Finding it hard to stop talking or interrupting

ADHD symptoms in children

Children with ADHD may show similar patterns, but they often appear differently in school or social settings.

Signs of inattention in children include:

Making more careless mistakes in their schoolwork
Losing books, pencils, or homework
Seeming as though they are not listening when spoken to directly, more often than their peers

Signs of hyperactivity or impulsivity in children include:

Fidgeting
Struggling to remain seated
Interrupting games
Finding it difficult to wait their turn
Running around or playing loudly in settings where it's not expected, again more often than their peers.

ADHD looks different for every child. Some show mostly inattentive symptoms, others show hyperactive‑impulsive symptoms, and some show both.

Psychologist conducting one-on-one assessment session with adolescent client in therapeutic office setting

ADHD medication

Medication is one of the treatment options doctors may consider for ADHD. Common approaches include stimulant and non‑stimulant medications, which can help improve focus, reduce impulsivity, and support daily functioning. A qualified healthcare professional can help determine whether medication is appropriate.

Understanding your ADHD

ADHD looks different for everyone. You don’t need to have signs of both inattention and hyperactivity‑impulsivity to be diagnosed.

However ADHD might present for you, you deserve to feel understood. Having ADHD doesn't mean your brain is broken. It's just built differently.

Dr Francesca Ulett, psychiatrist at Clear Psychiatry.

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