Can ADHD Be Diagnosed in Adulthood if Symptoms Were Not Recognised in Childhood? 

Yes, ADHD can be diagnosed in adulthood, even if childhood symptoms are missed. The late ADHD diagnosis is increasingly recognised in clinical practice, as many adults only realise they may have ADHD after struggling with symptoms for years. These individuals may have developed coping strategies to manage their symptoms, such as avoiding tasks that require sustained focus or using impulsivity to fuel productivity. As a result, adult ADHD recognition can be delayed until the demands of adulthood — like work or family responsibilities — make the symptoms more noticeable. 

The DSM-5 criteria for an ADHD diagnosis stipulate that symptoms must have been present before the age of 12. However, even if symptoms were not formally recognised in childhood, adults may still be diagnosed if there is sufficient evidence that the symptoms have been ongoing. This includes difficulties in attention, impulse control, and hyperactivity that persist into adulthood and cause significant impairment in daily functioning. 

Adults who suspect they have ADHD may find that their childhood symptoms were missed, often because they were less obvious or overlooked. Commonly, ADHD symptoms in children may be mistaken for laziness or other behavioural issues, leading to a late ADHD diagnosis in adulthood. 

How It Helps 

A late ADHD diagnosis can provide clarity for adults who have struggled with unrecognised symptoms for years. It can also offer access to targeted treatments, such as therapy or medication, which can significantly improve their quality of life and help them manage their symptoms effectively. 

Visit providers like ADHD Certify for personal consultations and expert advice tailored to your needs.   

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to DSM-5 Diagnostic Guidelines.