Can Adults Have ADHD Combined Type, and How Does It Present Differently Than in Children? 

Yes, adults can have ADHD Combined Type. This presentation of ADHD covers both inattentive and hyperactive-impulsive symptoms. Adult ADHD can go unnoticed for years behind coping mechanisms misattributed to stress, personality, or life events. It is important to identify the symptoms, particularly because the effects of combined ADHD change with age. This article explores how ADHD symptoms in adults compare to those seen in children, and what to look for. 

What Is Combined ADHD? 

Combined ADHD is one of three primary presentations of attention deficit hyperactivity disorder. To meet the diagnostic criteria, individuals must exhibit multiple symptoms from both the inattentive and hyperactive-impulsive categories. These symptoms must be persistent, impact daily functioning, and appear in more than one setting (e.g. work and home). Typical inattentive symptoms include losing focus, becoming easily distracted, and having difficulty finishing projects. Hyperactive-impulsive signs may include fidgetiness, excessive talking, or acting without thinking. These features taken together create combined ADHD, usually the most obvious and frequently diagnosed type. 

Can Adults Have Combined ADHD? 

Yes, adult ADHD is real and often underdiagnosed. Many adults who live with combined ADHD were not identified as children, particularly if their symptoms were mild or by relying on intelligence or external organisational strategies.  As adults, the hyperactivity of childhood hyperactivity often becomes internalised, felt as restlessness agitation, or racing thoughts, becomes reckless spending, poor decision-making, or difficulty maintaining relationships. These changes can make it harder for adults with ADHD to link current symptoms to childhood experiences 

How Combined ADHD Presents in Adults 

Common Traits 

• Disorganisation: Difficulty keeping on top of plans, appointments, or daily tasks. 

• Emotional dysregulation: Mood swings, frustration, and sensitivity to criticism. 

• Mental restlessness: Constant inner chatter, trouble relaxing, or a sense of being ‘on edge. 

• Impulsivity: Impulsive purchases, sudden career moves, or speaking without a filter. 

Challenges in Daily Life 

• Work: Struggling to stay focused or complete long-term projects. 

• Home environment: Neglected responsibilities, incomplete tasks, and stress resulting from misunderstandings. 

• Relationships: Incompatibility, impatience, or inconsistency in communication. 

• Burnout: Juggling too much, over-promising, and crashing from feeling overwhelmed. 

These are common challenges in adult ADHD, especially when combined ADHD is undiagnosed or untreated. 

How Combined ADHD Differs in Children 

Typical Signs in Children 

• Physical hyperactivity: Constant movement, fidgeting, and trouble sitting still. 

• Inattention: Struggles with listening, completing homework, or following instructions. 

• Impulsivity: Blurting answers, interrupting, or acting without thinking. 

• Social issues: Clashes with peers, frustration with rules, or being labelled as ‘disruptive’. 

Developmental Differences 

In children, behaviours are more external and noticeable, especially in school, where structure and peer comparison make differences obvious. As we grow older, many of the challenges we faced as children reappear in different forms what was once restlessness may evolve into anxiety, and school struggles can later manifest as burnout in the workplace. These patterns highlight that the contrast between ADHD vs child ADHD is about more than age it also involves lifestyle, expectations, and neurodevelopment. 

Adult vs Child ADHD: Key Differences 

Trait	Adults	Children
Hyperactivity	Internal restlessness	Physical movement and fidgeting
Diagnosis	Often delayed	Usually spotted in school
Emotional Signs	Masked or internalised	Overt and observable
Main Challenges	Relationships, work, life balance	Classroom behaviour, social conflict

These adult vs child ADHD contrasts help explain why so many adults go undiagnosed for years. 

Final Thoughts 

Adults can and do live with combined ADHD, yet many begin to understand it only later in life. Although the symptoms may not be as prominent as those in children, the underlying issues are equally significant. If any of this sounds familiar, a professional ADHD diagnosis can be the first step towards real clarity and change. Take our free ADHD self-assessment to start understanding your experience and visit our guides on Adult ADHD and ADHD in Children.