Fibromyalgia

Information

Fibromyalgia syndrome (FMS) is a chronic condition characterised by widespread pain, often accompanied by significant fatigue, sleep disturbance, cognitive difficulties (commonly referred to as “fibro fog”), reduced physical functioning, and psychological distress. It is estimated to affect around 2% of the global population, with approximately 1.8 to 2.9 million people in the UK living with fibromyalgia. The condition is more common in women than in men (Arthritis UK)

Current evidence suggests that fibromyalgia syndrome (FMS) involves abnormal pain processing, with increased sensitivity in both the central and peripheral nervous systems. Brain imaging shows heightened responses to normally non-painful stimuli, and small nerve fibre abnormalities may also contribute. Stressful life events can increase the risk of FMS, though many develop FMS without such triggers. A genetic component is also likely, as the condition can run in families.

Investigations:

There is no diagnostic investigation to make or confirm the diagnosis of Fibromyalgia.

FMS is not a diagnosis of exclusion and may co-exist with other conditions. However, investigations and assessment should be carried out to identify any other causes that might be also contributing to or exacerbating pain:

Blood tests** to look for causes based on clinical suspicion e.g. RA, SLE, AxSpA
Medication reviews that might be causing pain e.g. Statins
Screen for and treat conditions that can worsen widespread pain e.g. depression, anxiety

**RCP guidance recommended initial blood tests include FBC, ESR/CRP, U&Es, LFTs & Bone profile, CK, Glucose &TSH.

Diagnostic criteria

The evidence-based American College of Rheumatology (ACR) 2016 diagnostic criteria is the current diagnostic standard. (link to Fibromyalgia diagnostic worksheet)

To make a diagnosis using the ACR 2016 criteria the following need to be present*:

Widespread pain index (WPI) ≥7 & symptom severity scale (SSS) score ≥5 (OR WPI 4–6 and SSS score ≥9)
Generalised pain in ≥ 4/5 body regions
Symptoms have been present at a similar level for ≥ 3 months

*Download a copy of the Fibromyalgia Syndrome Diagnostic Worksheet (https://www.rcplondon.ac.uk/file/36231/download) for the patient to complete.

Differential Diagnosis and Other Considerations:

Before assessing patients for Fibromyalgia, it is important to be familiar with the types of pain:

Pain type	Nociceptive	Neuropathic	Nociplastic
Cause	Damaging or irritating stimuli to pain receptors	damage or disease affecting the nervous system itself	Pain that arises from altered pain processing in the nervous system.
Examples	Osteoarthritis, fracture	Sciatica, shingles, MS	Fibromyalgia, tension-type headache
May respond to	Standard analgesia e.g.NSAIDs, PCM	Neuropathic pain killers, nerve decompression.etc	May not respond to medications

Differential Diagnosis includes:

Endocrine disease (hypothyroidism)
Rheumatic conditions (e.g. ankylosing spondylitis, SLE, RA, PMR, Sjogren’s)
Neurological disease (e.g. neuropathies, myopathies, MS)
Drug-induced conditions (statins, aromatase inhibitors, opioid-induced hyperalgesia)
Sleep disorders e.g. OSA
Chronic fatigue syndrome
Depression

HB, FH & MA 26-08-26

**If diagnosis is clear, DO NOT refer for specialist opinion for confirmation of diagnosis**

When to Refer

If there is clear diagnostic uncertainty complicated by inflammatory rheumatological condition e.g. RA, SLE (otherwise consider referral to relevant specialty e.g. neurology if MS suspected etc)

When not to Refer

If diagnosis is clear or if you suspect a non-rheumatological problem

Fibromyalgia is frequently associated with significant emotional distress, decline in function and quality of life.

Therefore, following diagnosis, it is both good practice and essential to, arrange follow up with a health professional to review the individuals’ understanding of Fibromyalgia and develop shared management plan.

The diagnosis of fibromyalgia syndrome | RCP

Consider:

Screen and address any active mental health conditions eg PTSD, cPTSD, trauma, GAD, depression
Address social stressors as appropriate through third sector / AHP support
If pain is resulting in significant emotional distress and function, consider referral to pain management services for biopsychosocial support
Non-pharmacological approaches should be considered as the first step
A person-centred, multidisciplinary/interdisciplinary, biopsychosocial, approach is essential, combining exercise, Psychological therapies, patient education, and selective medication use to enhance quality of life and functional outcome,
Consider the context of the individual’s background, beliefs, fears, expectations; previous experiences of pain; causes and other aspects of their physical and mental health.

Patient Education:

Information leaflet (Reconnect2Life Fibromyalgia leaflet: https://www.torbayandsouthdevon.nhs.uk/uploads/what-is-fibromyalgia.pdf.

Medications play only a small role in the management.
Signpost the patient to the Arthritis UK and Flippinpain websites (see resources).
Paced physical activity should be advised as a recommended treatment for people living with chronic pain.

Pain Management Services:

For individuals experiencing emotional distress and functional limitation, consider referral to pain management services:

Physiotherapy Led Pain Management (East and West Lothian)

Provides pain education, management strategies and exercise progression. East Lothian have a Physiotherapist dedicated to chronic pain management https://apps.nhslothian.scot/refhelp/guidelines/musculoskeletalphysiotherapy/chronic-msk-pain-local-services/

Lothian Chronic Pain Management

Provides multidisciplinary Pain Psychology and Physiotherapy https://apps.nhslothian.scot/refhelp/guidelines/chronicpain/

Musculoskeletal Physiotherapy:

https://apps.nhslothian.scot/refhelp/guidelines/musculoskeletalphysiotherapy/

Clinical psychology:

Cognitive behaviour therapy (Consider referral via Silvercloud for Chronic Pain cCBT on Sci Gateway if appropriate)

Medications:

Refer to Chronic Pain Quality Prescribing Guide:https://www.gov.scot/publications/quality-prescribing-chronic-pain-guide-improvement-2026-2029/pages/4/

The mainstay of treatment is with patient education, pain management and physical therapy, The following medications may be considered in selected patients.

Duloxetine
Gabapentin is generally considered a second-line or adjunctive option, particularly for patients who have not responded to first-line treatments like exercise, cognitive-behavioral)
Amitriptyline
Nortriptyline
Fluoxetine
Analgesics and NSAIDs are seldom helpful

Health Care Professionals

Fibromyalgia syndrome diagnostic worksheet (fibromyalgia-syndrome-diagnostic-worksheet_1_0_0.pdf)

The diagnosis of fibromyalgia syndrome | RCP: https://www.rcp.ac.uk/improving-care/resources/the-diagnosis-of-fibromyalgia-syndrome/

Chronic Pain Quality Prescribing Guideline

https://www.gov.scot/publications/quality-prescribing-chronic-pain-guide-improvement-2026-2029

The diagnosis of fibromyalgia syndrome | RCP London (resources for clinicians and patients)

Fibromyalgia | Arthritis UK (https://www.arthritis-uk.org/information-and-support/understanding-arthritis/conditions/fibromyalgia/)

FMAUK information pack for health care professionals: http://www.fmauk.org/dmdocuments/Medical%20Pack.pdf

Management of Chronic Pain (SIGN): https://www.sign.ac.uk/guidelines/management-of-chronic-pain/

Chronic pain (primary and secondary) in over 16s: assessment of all chronic pain and management of chronic primary pain (NICE)
https://www.nice.org.uk/guidance/ng193/chapter/Recommendations

Primary Care Chronic Pain Management MDT

Chronic pain learning toolkit | Turas | Learn