Category · F40-F48 block
F45 — Somatoform disorders
Terminology note: Somatoform disorders involve repeated presentation of physical symptoms, or persistent preoccupation with the possibility of having a serious physical illness, together with persistent requests for medical investigation despite repeated negative findings and reassurance. The symptoms are genuinely experienced, not feigned, but are not adequately explained by an identifiable physical condition.
What is this category?
F45 covers presentations centred on physical symptoms or illness preoccupation not adequately explained by physical disease. Somatization disorder (F45.0) involves multiple, recurrent, and frequently changing physical symptoms across multiple organ systems, over years. Hypochondriacal disorder (F45.2) involves a persistent, fixed preoccupation with the possibility of having one or more specific serious diseases, maintained despite appropriate medical reassurance.
Core diagnostic concept
A somatoform disorder requires that an adequate medical work-up has genuinely been carried out and has not explained the symptoms or has not resolved the person's preoccupation, not merely that symptoms are currently unexplained or that investigation has not yet been completed. Confusing 'not yet explained' with 'adequately investigated and excluded' is this category's single most important error to avoid.
Key diagnostic features
- Multiple, recurrent physical symptoms (somatization disorder)
- Symptoms recur and change across multiple organ systems over a period of years.
- Persistent illness preoccupation despite reassurance (hypochondriacal disorder)
- A fixed conviction of having a specific serious disease, maintained despite appropriate medical reassurance and negative investigation.
- Adequate medical work-up genuinely completed
- The category requires that appropriate investigation has actually been carried out and has not adequately explained the symptoms — not simply that no explanation has yet been found.
- Genuine distress and repeated help-seeking
- The person genuinely experiences the symptoms as real and distressing and persistently seeks medical attention, rather than feigning them.
How to weigh evidence
These learning labels are teaching aids, not official ICD-10 terminology (see Sources and Method).
- supports Years of multiple, recurring physical complaints across different organ systems, with repeated medical investigation genuinely completed and not explaining the symptoms.
- consistent not decisive A person reports several physical symptoms without yet enough detail on whether an adequate medical work-up has actually been carried out.
- raises alternative A specific, previously undetected medical condition is subsequently found to explain the symptoms.
- contradicts or weakens Symptoms resolve fully once an underlying medical condition is identified and treated, arguing against a somatoform disorder.
- missing and necessary to ask Whether an adequate medical work-up has actually been completed and has genuinely not explained the symptoms, rather than investigation simply being incomplete or still pending.
Diagnostic boundary
F45 requires physical symptoms or illness preoccupation not adequately explained by physical disease after a genuinely adequate medical work-up — never assumed simply because a symptom is not yet explained or has not yet been fully investigated.
Full comparisons:
Duration and course
Minimum duration: Somatization disorder: conventionally at least two years of multiple, recurring symptoms. Hypochondriacal disorder: a persistent preoccupation, typically also sustained over months to years.
Course: Often chronic and fluctuating, with a pattern of repeated medical consultation.
Included presentations
- Somatization disorder: multiple, recurrent, frequently changing physical symptoms across multiple organ systems, over years.
- Undifferentiated somatoform disorder: a similar but less extensive or persistent pattern than full somatization disorder.
- Hypochondriacal disorder: persistent preoccupation with having one or more specific serious diseases, despite reassurance.
- Somatoform autonomic dysfunction: symptoms referable to an organ system under autonomic control, without adequate organic explanation.
- Persistent somatoform pain disorder: persistent, severe pain not adequately explained by a physical or physiological process.
Exclusions and distinguishing presentations
| If this is true instead… | Consider | Why |
|---|---|---|
| Physical symptoms without an adequate medical work-up genuinely having been completed | unexplained symptoms default to somatoform | A somatoform classification requires that appropriate investigation has actually been carried out and has not explained the symptoms — not simply that investigation is incomplete or still pending. |
| A specific, sudden loss of a function (memory, movement, or sensation) rather than multiple recurring bodily complaints or a fixed illness conviction | F44 | F44's dissociative disorders involve a discrete functional loss; F45's somatoform disorders involve recurring physical complaints or illness preoccupation without a discrete functional loss. |
Four-character subtypes (orientation)
A learner should never default to a somatoform classification simply because a symptom is currently unexplained — the category requires that an adequate medical work-up has genuinely been completed and has not explained the presentation.
- F45.0 — Somatization disorder
- Multiple, recurrent, changing physical symptoms across multiple organ systems, over years. (in_depth)
- F45.1 — Undifferentiated somatoform disorder
- A similar but less extensive or persistent pattern than full somatization disorder. (taught for orientation only, not separately assessed in this pilot)
- F45.2 — Hypochondriacal disorder
- Persistent preoccupation with a specific serious disease despite reassurance. (in_depth)
- F45.3 — Somatoform autonomic dysfunction
- Symptoms referable to an autonomically-controlled organ system, without organic explanation. (taught for orientation only, not separately assessed in this pilot)
- F45.4 — Persistent somatoform pain disorder
- Persistent, severe pain not adequately explained physically. (taught for orientation only, not separately assessed in this pilot)
- F45.8 — Other somatoform disorders
- A somatoform presentation not matching the named subtypes. (taught for orientation only, not separately assessed in this pilot)
- F45.9 — Somatoform disorder, unspecified
- A somatoform disorder identified but without enough information to specify further. (taught for orientation only, not separately assessed in this pilot)
External causes to check first
Categories in this block require that the disturbance is not better explained by another external cause listed below. These short capsules are reminders, not full teaching modules.
External cause capsule — Organic, medical, or substance-related presentations resembling F40-F48
A reminder that a presentation resembling an anxiety, obsessive-compulsive, stress-related, dissociative, or somatoform disorder can instead be caused by a general medical condition (e.g. hyperthyroidism producing anxiety-like symptoms, a neurological condition producing genuine sensory or motor loss) or a substance/medication (e.g. caffeine or stimulant intoxication, sedative or alcohol withdrawal producing anxiety symptoms) rather than being a primary F40-F48 disorder, and that this should be actively considered before a primary F40-F48 classification is settled.
What to check:
- Timing: did the symptoms begin during or shortly after starting, stopping, intoxication with, or withdrawal from a substance or medication known to produce anxiety, dissociative, or somatic symptoms?
- Medical context: is there a known medical or neurological condition (e.g. thyroid disease, a cardiac arrhythmia, a neurological lesion) with a recognised association with the symptoms described?
- Adequacy of investigation: has an appropriate medical or neurological work-up actually been completed, rather than simply not yet undertaken?
- Course after the cause is addressed: symptoms that substantially improve once the medical condition is treated or the substance/medication is stopped weigh toward a secondary cause rather than a primary F40-F48 disorder.
A full teaching module on F00-F09 (organic mental disorders) or F10-F19 (substance-related disorders), or a general medical work-up, all of which are outside this capsule's scope.
Worked example — confirming an adequate work-up before a somatoform classification
A 46-year-old has, over the past six years, presented repeatedly with changing physical complaints — abdominal pain, joint pain, palpitations, and dizziness — each investigated thoroughly by different specialists with normal findings each time, including repeat blood tests, imaging, and cardiac work-up. She continues to seek reassurance and further tests despite being told repeatedly that no physical cause has been found, and the symptoms cause significant distress and repeated time off work.
- Step 1 — Note the pattern: multiple, recurring, changing physical symptoms across different organ systems (gastrointestinal, musculoskeletal, cardiac, neurological) over six years.
- Step 2 — Confirm an adequate work-up: repeated, thorough investigation by multiple specialists, with normal findings each time.
- Step 3 — Note the genuine distress and repeated help-seeking, distinguishing this from feigning.
- Conclusion — F45.0, Somatization disorder — a genuinely adequate medical work-up has been completed and has not explained the recurring, multi-system physical complaints.
Interactive practice
- Type A Six years, many specialists, no answer Recognition / application · Foundation
- Type B Convinced it's cancer Boundary discrimination · Developing
- Type C New complaints, work-up still pending Insufficient information · Developing
Retrieval prompts
Try answering each of these from memory before revealing where to check. Nothing you think or type here is sent or saved anywhere.
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Explain why 'not yet explained' is not the same as 'adequately investigated and excluded.'
Reveal answer location
Check Duration and course, Diagnostic boundary, or the rapid revision card below — the cue you need is one of those, in this category's own already-authored wording.
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Distinguish somatization disorder from hypochondriacal disorder in one sentence.
Reveal answer location
Check Duration and course, Diagnostic boundary, or the rapid revision card below — the cue you need is one of those, in this category's own already-authored wording.
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State roughly how long somatization disorder's symptom pattern conventionally needs to have persisted.
Reveal answer location
Check Duration and course, Diagnostic boundary, or the rapid revision card below — the cue you need is one of those, in this category's own already-authored wording.
These self-checks are a personal study aid only, visible to you on this page for this visit — they are not stored and do not affect your mastery dimensions.
Rapid revision card
F45: F45 requires physical symptoms or illness preoccupation not adequately explained by disease after a genuinely completed medical work-up.
Decisive boundary cues:
- Multiple, recurring, changing symptoms across organ systems over years, adequately investigated -> weighs toward F45.0.
- A fixed conviction of one specific serious disease despite reassurance -> weighs toward F45.2.
- Investigation genuinely incomplete or still pending -> the classification cannot yet be confirmed, and more information should be sought.
Duration/course: Somatization disorder: conventionally at least two years. Hypochondriacal disorder: a sustained preoccupation over months to years.
Nearest alternatives: f44, f48
Common mistake: Defaulting to a somatoform classification for physical symptoms that are simply not yet explained, without confirming that an adequate medical work-up has actually been completed.
Retrieval prompt: Has an adequate medical work-up genuinely been completed and failed to explain these symptoms, or is investigation simply still incomplete?
(or use your browser's print function) Open full-page printable revision view →
Related glossary terms
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Somatization
The genuine experience and reporting of physical symptoms that are not adequately explained by an identifiable physical condition after appropriate medical investigation, often accompanied by persistent help-seeking despite negative findings and reassurance. Multiple, recurrent, changing somatization over years, across multiple organ systems, defines somatization disorder (F45.0).
Source basis
WHO ICD-10 international classification structure and code/title (ICD-10 Browser, 2019 English release).
Original educational synthesis, informed by general published clinical-education understanding of ICD-10 F40-F48; no verbatim CDDG or DCR text is reproduced. See Sources and Method for the full policy.
Last reviewed: 2026-09-16. Full policy: Sources and Method.
Educational resource only. This page and its cases teach ICD-10 classification reasoning using fictional scenarios. It does not diagnose real people and should not be used to assess yourself or anyone else. If you or someone you know is struggling with anxiety, intrusive thoughts, the effects of a stressful or traumatic event, or persistent physical symptoms, please seek prompt professional evaluation.