Illness anxiety disorder

Persistent fear of serious illness despite minimal symptoms and repeated reassurance

RoutineReview due

At a glance

High-risk causes: 4
Related differentials: 8

Safety snapshot

Watch forEscalating investigationssevere avoidancehidden OCD/depressionHealthcare overutilisationescalating investigationssevere avoidance

Presentation hinge

Driven by excessive time, energy, and distress around symptoms, not by symptoms being fake.

Separates the Somatic Symptoms / Illness Anxiety / Functional Neurological Symptoms / Factitious Presentation group. It is not specific to Illness anxiety disorder.

Clinical review

Rows marked “Whole group”: Applies to the Somatic Symptoms / Illness Anxiety / Functional Neurological Symptoms / Factitious Presentation group — not specific to Illness anxiety disorder

Why it fits

Persistent fear of serious illness despite minimal symptoms and repeated reassurance

Key features2 features

Persistent fear of having/acquiring serious illness despite minimal somatic symptoms
Abrupt peak over minutes, recurrent unexpected attacks, anticipatory anxiety or avoidance.

Must-not-miss

Healthcare overutilisation, escalating investigations, severe avoidance.

High-risk causes4 causes

Escalating investigations
severe avoidance
hidden OCD/depression
Healthcare overutilisation

Bedside question

Applies to the Somatic Symptoms / Illness Anxiety / Functional Neurological Symptoms / Factitious Presentation group.

Driven by excessive time, energy, and distress around symptoms, not by symptoms being fake.

Helpful clues1 clue

Abrupt peak over minutes, recurrent unexpected attacks, anticipatory anxiety or avoidance.

Immediate action

Applies to the Somatic Symptoms / Illness Anxiety / Functional Neurological Symptoms / Factitious Presentation group.

None listed

Priority steps

Investigations

Applies to the Somatic Symptoms / Illness Anxiety / Functional Neurological Symptoms / Factitious Presentation group.

None listed

Core tests

Mimics / overlap

Applies to the Somatic Symptoms / Illness Anxiety / Functional Neurological Symptoms / Factitious Presentation group.

None listed

Consider

Clinical reference — not validated decision support. Review before use.