Synopsis
Recognise autism and ADHD within child mental-health presentations, distinguish neurodevelopmental traits from new illness, adapt assessment and environments, identify physical and safeguarding drivers of distress, and coordinate safe specialist treatment without diagnostic overshadowing.
- Autism is characterised by persistent differences in social communication and interaction alongside restricted or repetitive patterns, sensory features or need for sameness arising in development; presentation varies widely.
- ADHD requires developmentally inappropriate inattention and/or hyperactivity-impulsivity causing significant impairment across settings; a rating scale or brief observation cannot diagnose it alone.
- Establish the young person's ordinary communication, sensory, sleep, activity, eating and behavioural baseline before interpreting a crisis or mental-state examination.
- Diagnostic overshadowing occurs when new depression, anxiety, psychosis, trauma, epilepsy, pain or abuse is incorrectly attributed to autism, ADHD or learning disability.
- Use concrete language, extra processing time, visual structure, predictable sequencing, sensory adjustments and the person's preferred communication method as clinical necessities.
- NICE advises systematic assessment for coexisting mental, neurodevelopmental, physical and functional conditions in autistic children and young people.
- ADHD medication must be initiated by a trained specialist after baseline mental, social and physical assessment; ECG is not routine unless specific cardiac or medication risks are present.
- During an acute psychotic or manic episode, NICE advises stopping ADHD medication and reconsidering it after the episode resolves using individual risks and benefits.
- For severe behaviour that challenges in autism, assess triggers and use psychosocial or environmental intervention first; antipsychotic treatment is specialist, target-based and stopped at six weeks if no important response.
Key red flags
Loss of previously acquired language or motor skills, altered consciousness, new focal signs, seizure or marked cognitive change needs urgent paediatric or neurological assessment.
A new sustained reduction in sleep with grandiosity, psychosis, severe agitation or disorganised behaviour must not be explained away as ADHD hyperactivity or autistic difference.
Self-injury, aggression or withdrawal may signal pain, constipation, dental disease, infection, trauma, bullying, medication effects or sensory overload and needs active cause-finding.
Food or fluid refusal, dehydration, rapid weight change, sleep collapse or inability to complete basic care can create medical danger even when behaviour appears familiar.
Restraint, seclusion, exclusion from school, exploitation or repeated police contact should prompt review of unmet communication, environmental and safeguarding needs.
Investigation priorities
Map early development, traits, strengths, communication, sensory needs and ordinary function across settings.
Management branches
An autistic or ADHD young person is distressed, withdrawn, agitated or unable to engage in a mental-health setting.
- Reduce noise, light, crowding, language and unpredictable touch; offer the preferred communication method and a familiar supporter when safe.
- Establish baseline and assess pain, physical illness, sleep, intake, medication, trauma, mental state, self-harm and safeguarding.
- Treat the identified emergency and write the adjustments and early warning signs into the shared care plan for future encounters.