Somatic and functional disorders: the AU general practice approach

Somatic and functional disorders are responsible for a substantial proportion of Australian general practice workload. Medically unexplained symptoms — physical symptoms without a fully adequate biomedical explanation — account for 15–30% of consultations in some estimates. This does not mean the symptoms are not real; it means the mechanism involves the nervous system’s processing of sensation rather than structural tissue damage detectable on current investigations.

Understanding the modern diagnostic framework matters for patient outcomes. Outdated approaches — “we couldn’t find anything wrong,” prolonged investigation cascades, implicit or explicit dismissal — cause substantial harm. eTG complete and the RACGP support the positive diagnostic framework articulated in DSM-5 and the growing neurobiological literature on central sensitisation and functional neurological disorder.

A. Core clinical — the AU general-practice framework

DSM-5 somatic symptom and related disorders

Somatic symptom disorder (SSD):

• ≥1 distressing somatic symptom causing impairment
• Excessive thoughts, feelings, or behaviours related to symptoms or health concerns, operationalised as at least one of:
  • Disproportionate persistent thoughts about the seriousness of symptoms
  • Persistently high anxiety about health or symptoms
  • Excessive time or energy devoted to symptoms or health concerns
• Duration ≥6 months (specific symptoms may change over time)
• Coexisting medical illness does not exclude the diagnosis — a patient with genuine cardiac disease can also have SSD

Illness anxiety disorder (IAD) (formerly hypochondriasis in most):

• Preoccupation with having or acquiring a serious illness, despite mild or absent somatic symptoms
• High health anxiety and excessive checking or avoidance behaviours
• ≥6 months

Functional neurological disorder (FND / conversion disorder):

• ≥1 neurological symptom of altered voluntary motor or sensory function
• Positive clinical findings showing incompatibility with recognised neurological disease — FND is NOT a diagnosis of exclusion (Stone et al., Brain 2018)
• Significant distress or impairment

The DSM-5 shift (2013) away from requiring exclusion of medical disease towards positive identification of excessive health-related cognition and behaviour was grounded in clinical research and clinically important. Patients with physical illness can develop SSD; the diagnosis captures the excessive response, not the absence of pathology.

Functional somatic syndromes cluster

A related set of conditions — sometimes called central sensitivity syndromes — share overlapping pathophysiology of central nervous system sensitisation, descending pain modulation impairment, and autonomic dysregulation:

• Irritable bowel syndrome (IBS)
• Fibromyalgia
• Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)
• Chronic pelvic pain
• Temporomandibular joint dysfunction
• Vulvodynia
• Interstitial cystitis
• Postural orthostatic tachycardia syndrome (POTS)
• Hypermobility spectrum disorders (hEDS overlap)
• Mast cell activation syndrome (MCAS overlap)

Patients frequently have more than one of these conditions simultaneously. Trauma history — particularly childhood adversity — is common. Genetic clustering in families has been demonstrated.

Functional neurological disorder — recognising the positive signs

FND has specific positive diagnostic findings that can be demonstrated at the bedside. Recognising these changes the consultation from “I can’t find anything wrong” to “here’s the test that shows me exactly what’s happening.”

Hoover’s sign (functional leg weakness):

• Test involuntary hip extension in the weak leg by pressing down on the heel of the normal leg against resistance
• If hip extension in the weak leg occurs during this manoeuvre, it demonstrates intact motor pathways — the voluntary weakness is due to abnormal motor planning, not structural nerve or muscle damage

Tremor entrainment (functional tremor):

• Ask the patient to make a rhythmic tapping movement with the unaffected hand at a set pace
• Functional tremor entrains to the tapping frequency (or disappears); organic tremor does not change

Eye closure resistance (functional seizures):

• During an episode, functional seizures typically show active resistance when the examiner attempts to open the eyelids
• Epileptic seizures do not produce active resistance

Inconsistency with distraction: functional motor and sensory symptoms vary with attention — better when distracted, worse when focused.

History and examination

A thorough history targeting the pattern of symptoms, triggers, and the relationship between symptoms and psychological states is essential. Specifically:

• Onset and precipitant — acute onset often following a physical event (minor injury, viral illness, medical procedure) or significant life stressor
• Pattern — symptoms that vary with attention, stress, or psychological state
• Timeline — often chronic from a relatively fixed onset
• Previous investigations — extent of prior workup; prior diagnoses
• Trauma history — sensitively enquired; childhood adversity, assault, major life trauma
• Comorbidities — depression (PHQ-9), anxiety (GAD-7), PTSD screen, substance use
• Healthcare experience — multiple clinicians, multiple diagnoses, conflicting messages, prior dismissal

Examination serves two purposes: excluding medical mimics and demonstrating positive functional signs.

B. Evidence on management — what works and what harms

Communication and diagnosis

The single most important intervention is clear, positive, validating communication of the diagnosis. Stone et al. (Brain 2018) demonstrated that explanation of the diagnosis, when framed positively and matched with demonstrating the positive clinical sign, is itself therapeutic — it reduces anxiety, healthcare utilisation, and symptom amplification.

Key elements:

• “This is a recognised condition” — naming it removes the void of uncertainty
• “Your brain has developed a problem with how it controls movement/processes sensation — not damage to the nerves or muscles themselves”
• “This is real — I’m not suggesting it’s imagined”
• “There are effective treatments”
• Share Neurosymptoms.org for FND

What to avoid: “there’s nothing wrong,” “it’s psychosomatic” (without explanation), “stress is causing this” (without neurobiological framing), “the tests were all normal” as the only response.

CBT and psychological therapies

CBT adapted for somatic concerns and health anxiety has the strongest evidence base across SSD and IAD — Cochrane reviews demonstrate moderate effect sizes for symptom reduction, health anxiety, and healthcare use reduction. Acceptance and commitment therapy (ACT) is particularly valuable when the primary problem is catastrophising and distress about distress. CBT referral via Mental Health Care Plan (MBS items 2715/2717) is the appropriate pathway.

FND-specific physiotherapy — a distinct specialisation from standard physiotherapy — has RCT evidence (Nielsen et al., Stone et al.) for functional motor disorders. Referral to an FND-trained physiotherapist (access growing in Australia via FND Hope Australia) is recommended alongside psychotherapy.

Pharmacotherapy

Pharmacotherapy addresses comorbidities, not SSD directly:

• SSRIs or SNRIs for comorbid depression or anxiety — General Schedule; standard treatment, not a specific SSD drug
• Low-dose amitriptyline (10–25 mg nocte) — Cochrane evidence in fibromyalgia, IBS-associated pain, neuropathic pain; modulates descending pain pathways
• Duloxetine — evidence in fibromyalgia, neuropathic pain; Authority Required for specified neuropathic pain indications
• Pregabalin or gabapentin — Authority Required for neuropathic pain; SafeScript-monitored; relevant diversion and dependence risk — prescribe cautiously and with clear review plans
• Opioids — avoid in somatic and functional disorders; NICE NG193 recommends against; opioid-induced hyperalgesia worsens central sensitisation; SafeScript and Real-Time Prescription Monitoring (RTPM) apply
• Benzodiazepines — tolerance, dependence, disinhibition; avoid as first-line or chronic therapy in somatic disorders

What harms patients

• Repeated unnecessary investigations — reinforces “something wrong but undetected” cognition
• Facilitated diagnostic shopping across multiple specialists
• Polypharmacy without structured review
• Opioid and benzodiazepine prescribing
• Lack of consistent therapeutic relationship
• Dismissal or disbelief

C. Functional somatic syndromes — specific management notes

IBS: CBT, low-FODMAP dietary approach (dietitian referral), low-dose amitriptyline or mebeverine for pain, RACGP IBS guidelines.

Fibromyalgia: graduated exercise (walking, water aerobics), CBT, amitriptyline 10–25 mg nocte, duloxetine, pregabalin (with caution), multidisciplinary pain programme.

ME/CFS: pacing and activity management is foundational — “boom-bust” cycles worsen post-exertional malaise; graded exercise requires specialist guidance and should not be applied if there is significant post-exertional malaise; CBT for fatigue management; Royal Australian College of Physicians guidance.

POTS: increased salt and fluid intake, compression garments, graduated upright exercise programme, beta-blockers or fludrocortisone in refractory cases (specialist cardiologist or neurologist).

D. Australian operations

MBS items

• Item 23 — Level B GP attendance
• Item 36 / 44 — longer Level C / D consultations (these patients routinely need more time)
• Item 2715 / 2717 — Mental Health Care Plan (preparation and review)
• Item 80000–80020 — psychology Better Access (10 subsidised sessions/year)
• Item 81335 — telehealth psychology
• Item 132 / 133 — consultant physician (psychiatry) initial and subsequent
• Item 291 / 293 — psychiatrist consultation
• Item 965 / 967 — GPCCMP (replacing GPMP/TCA from 1 July 2025); valuable for chronic complex somatic presentations requiring allied health coordination
• Item 10960 — allied health services under EPC plan (physiotherapy, OT)
• Item 10968 — exercise physiology under EPC plan

PBS prescribing

• SSRIs, SNRIs — General Schedule (comorbid depression/anxiety)
• Amitriptyline, nortriptyline — General Schedule
• Duloxetine — Authority for major depression, GAD, diabetic peripheral neuropathic pain
• Pregabalin, gabapentin — Authority for neuropathic pain; SafeScript/RTPM monitored
• Opioids, benzodiazepines — SafeScript/RTPM monitored; avoid in SSD and functional disorders

Specialist referral pathways

• Psychologist (CBT or ACT-trained) — first-line; specify somatic focus or chronic illness experience in referral
• FND clinics — Royal Melbourne Hospital, Royal Prince Alfred Hospital Sydney
• Multidisciplinary pain clinic — chronic functional pain overlapping with CPSP
• Neurologist — initial FND diagnosis confirmation; ongoing input as needed
• Psychiatrist — complex comorbidity, refractory cases

Australian patient resources

• Neurosymptoms.org (Jon Stone) — the best patient resource for FND; free, comprehensive, research-grounded
• FND Hope Australia / FND Australia — patient organisation; peer support; information
• MindSpot — free Macquarie University internet-delivered CBT for anxiety, depression, chronic pain; no GP referral required
• This Way Up — AU-developed iCBT; anxiety, depression, chronic pain programmes
• Tame the Beast (Lorimer Moseley, UniSA) — pain neuroscience education; freely accessible
• Pain Australia — patient organisation for chronic pain
• Chronic Pain Australia — peer support and advocacy

E. Special populations

Adolescents and young adults. Functional symptoms including functional seizures (PNES) and functional weakness are more common in young women. Trauma-informed and developmentally appropriate communication is essential. Paediatric neurology or adolescent psychiatry referral may be appropriate.

Patients with established medical illness. SSD and medical illness commonly co-exist. Patients with multiple sclerosis, lupus, cardiac disease, or cancer can also have SSD overlaid. The challenge is not to attribute all symptoms to the SSD diagnosis and miss new organic developments — periodic re-evaluation and willingness to revise the formulation are essential.

Aboriginal and Torres Strait Islander patients. Trauma history including intergenerational trauma and experiences of racism within healthcare are prevalent. A trauma-informed, culturally safe approach is foundational. Engagement with Aboriginal Community Controlled Health Organisations (ACCHOs) supports holistic, community-centred care.

Patients with disability support or workers’ compensation claims. Document objectively, focus on functional capacity rather than symptom counts, and provide consistent communication across the treating team. Avoid colluding with secondary gain framing — most patients with SSD are not deliberately producing symptoms — but attend to system factors that may inadvertently reinforce illness behaviour.

When to escalate

Urgent psychiatric referral when: active suicidal ideation, severe self-harm, acute psychosis, or decompensated major depression are identified alongside somatic presentations.

Routine neuropsychiatry or FND clinic: confirmed or suspected FND with functional disability not improving with explanation and brief intervention.

Pain medicine specialist or multidisciplinary pain programme: chronic functional somatic pain with significant functional impairment.

Revise the diagnosis and reinvestigate if: new organic symptoms emerge, examination findings change, or the presentation does not fit the established pattern. Anchoring to a somatic/functional diagnosis can result in missed organic disease.

What this article is and is not

This article is general health information based on eTG complete, the RACGP, NICE NG10 and NICE NG193, Stone et al. (Brain 2018), the FND Society, RANZCP guidelines, and Cochrane systematic reviews. It is not personal medical advice and does not create a doctor–patient relationship.

For Australian consumer resources: Neurosymptoms.org, MindSpot, This Way Up, HealthDirect.

For mental health crisis: Lifeline 13 11 14, Beyond Blue 1300 22 4636, 13YARN 13 92 76 (First Nations).

---

Sources cited

1. eTG complete — Somatic symptom and functional disorders
2. RACGP — Functional disorders in general practice (AFP)
3. NICE NG10 — Persistent physical symptoms: assessment and management
4. NICE NG193 — Chronic primary pain
5. Stone J et al. — Functional neurological disorder (Brain 2018)
6. Neurosymptoms.org — Patient education for FND (Jon Stone)
7. FND Society — International clinical practice guidelines
8. RANZCP — Psychotherapy guidelines for functional somatic syndromes
9. Cochrane Library — Psychological treatments for somatic symptom disorders
10. DSM-5-TR — Somatic Symptom and Related Disorders
11. MindSpot — Free internet-delivered CBT (Macquarie University)
12. This Way Up — AU-developed iCBT
13. Pain Australia
14. HealthDirect