Mental Health

Autism spectrum disorder

Autism is a lifelong neurodevelopmental difference involving persistent social-communication and interaction differences together with restricted, repetitive patterns of behaviour, interests or activities, present from the early developmental period and associated with support needs or functional impact.

In a nutshell

Autism is a lifelong neurodevelopmental difference involving both social-communication and interaction differences and restricted, repetitive patterns of behaviour, interests or activities, present from the early developmental period. Diagnosis is specialist and clinical; tools support referral or complex assessment but do not diagnose alone. Management is person-centred and focuses on communication, environmental adjustments, life skills, comorbidity, sleep, nutrition, safeguarding and behaviour that challenges. No medication treats the core features; antipsychotics and melatonin have narrow specialist indications and require measurable goals and review.

Classic presentation

A child or adult has a lifelong pattern of social-communication difference and restricted or repetitive behaviour or interests, with sensory or routine-related needs and functional impact. Assessment integrates developmental history, collateral information, direct observation and coexisting physical and mental health; a fluent or apparently coping adult is not excluded.

Key points

Both core domains are required: social communication and interaction differences plus restricted, repetitive behaviours, interests or activities.
Features arise in the early developmental period but may be recognised only when social or occupational demands increase; masking does not exclude autism.
Diagnosis is clinical and multidisciplinary; screening tools, AQ-10, ADOS or ADI-R support assessment but do not diagnose or rule out autism alone.
Regression, seizures, acute behaviour change, severe self-injury, safeguarding risk, restricted diet or unexplained pain require targeted medical or safety assessment.
There is no drug treatment for core autistic features. Treat coexisting conditions and use functional, psychosocial and environmental approaches for behaviour that challenges.
Specialist antipsychotic treatment is a time-limited, measurable trial only after psychosocial approaches are insufficient or impossible because behaviour is severe; review at 3 to 4 weeks and stop at 6 weeks without clinically important response.
For children, use a sleep plan before specialist melatonin; assess feeding, growth, hydration and nutritional deficiency, and plan transition and reasonable adjustments around the person's needs.

First-line investigation

Specialist developmental and multidisciplinary autism assessment with collateral history, direct observation and assessment of support needs, coexisting conditions, sensory needs and function; use targeted hearing, vision, EEG or genetic assessment only when clinically indicated.

Management

Assess, explain and adapt care

Use a specialist developmental and multidisciplinary assessment with collateral history and direct observation; provide an accessible explanation, health passport or crisis plan where useful, and coordinate education, health, mental-health and social-care support.^1,2,7
Make communication and environmental adjustments explicit: predictable structure, visual or written information, sensory adaptations, reasonable adjustments and person-preferred involvement of family or carers.^5,2,9

Treat needs and behaviour by function

Investigate pain, constipation, sleep, seizures, mental disorder, communication difficulty, sensory overload, routine change and safeguarding concerns before attributing distress or behaviour that challenges to autism.^5,2
Use an individualised psychosocial intervention based on functional analysis, defined target behaviours, quality-of-life outcomes, environmental modification and systematic review.^5,2,8

Reserve medication for narrow indications

Do not use medicines for core autistic features. Consider a specialist antipsychotic for severe behaviour that challenges only after psychosocial or other interventions have been insufficient or could not be delivered; use measurable goals and the lowest effective exposure.^5,2,6,10
Review at 3 to 4 weeks and discontinue at 6 weeks if there is no clinically important response; monitor physical health, adverse effects, quality of life, target behaviours and the stopping plan.^5,2,8

Protect sleep, nutrition and mental health

Use a behavioural sleep plan first in children; specialist melatonin is considered only when sleep remains harmful despite the plan, alongside non-pharmacological measures and regular review. Assess restrictive diet, growth, hydration and nutritional deficiency.^5,10
Treat ADHD, anxiety, depression, eating disorder, epilepsy and physical illness using adapted NICE pathways; use urgent mental-health and safeguarding escalation for suicidality, psychosis, severe self-injury, exploitation or loss of safety.^5,2,11

Plan transition and review support needs

Reassess support around adolescence and adult transition, covering education, employment, housing, daily living, driving, relationships, carers, crisis planning and continuity between services.^5,2,4

Exam traps

Both diagnostic domains are required; isolated language delay, ADHD or social anxiety does not establish autism, although these conditions can coexist.
A screening score, ADOS, ADI-R or a negative childhood history alone does not make or exclude the diagnosis; interpret developmental and cross-context evidence clinically.
Do not attribute regression, seizures, pain, constipation, sleep apnoea, restricted diet or sudden behaviour change to autism without targeted medical assessment.
Antipsychotics do not treat core autistic features; for behaviour that challenges, identify physical, mental-health, communication and environmental triggers first.
If an antipsychotic is used, define target behaviour and quality-of-life outcomes, review at 3 to 4 weeks and stop at 6 weeks if no clinically important response.
Melatonin in autistic children is specialist advice after a sleep plan has failed and should be combined with non-pharmacological measures and regularly reviewed.
Respect preferred language, communication needs and autonomy; a person who masks or appears socially fluent may still need substantial support.

Key sources

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.