ADHD and autism together: overlap, assessment and support

Both are neurodevelopmental conditions with strong genetic influences and shared features, such as differences in attention, executive function, sensory processing and emotional regulation. Past diagnostic frameworks did not allow both to be diagnosed in the same person, which delayed recognition. Today clinicians can diagnose both where criteria are met.

• Wanting routine and predictability but struggling to maintain it.

• Intense focus on interests alongside difficulty starting or switching tasks.

• Sensory sensitivity combined with seeking stimulation.

• Impulsivity and social misunderstandings.

• Strong emotional responses with difficulty identifying them.

• Exhaustion from masking and from managing competing needs.

A thorough assessment considers developmental history, current functioning and the person's own account. Because each condition can mask or mimic the other, some services assess for both together. If you have been diagnosed with one and symptoms continue, you can ask your clinician whether the other has been considered. NICE guidance for ADHD and autism describes assessment by trained clinicians and consideration of co-occurring conditions.

ADHD medication may improve attention and impulse control in people with both conditions, though evidence is more limited than in ADHD alone. Some autistic people are more sensitive to side effects such as anxiety or irritability. Prescribers often start low and adjust slowly. Medication does not treat autism itself and is only part of the plan.

Strategies that help include visual schedules, body-doubling, external reminders, low-sensory spaces, predictable routines with built-in flexibility, planned recovery time and clear communication. Occupational therapy can help with sensory and daily living needs. Peer groups for people with both conditions offer recognition and ideas.

Reasonable adjustments should address both sets of needs, for example written instructions, flexible deadlines, quiet workspace and structured check-ins. In education, specialist support and, for university students in England, Disabled Students' Allowance may be available with appropriate evidence. Share assessment reports to explain how the combination affects you.

If you suspect that both conditions apply, it can help to prepare a short list before you see a clinician. Ask whether the service assesses both together, how they will separate overlapping features, whether co-occurring anxiety or depression will be reviewed and how treatment decisions will take both conditions into account. Ask too what happens if you receive one diagnosis and the other is left open, because follow-up assessment may need a new referral. Write down which of your difficulties worry you most, since the plan should be built around those priorities rather than around labels alone. Take a trusted person if that helps you remember the answers.