What are the symptoms and treatment options for fibromyalgia?

Fibromyalgia: Symptoms and Treatment

Core Clinical Symptoms

Fibromyalgia is characterized by chronic widespread pain (lasting >3 months) affecting all four body quadrants, accompanied by a constellation of associated symptoms that significantly impair quality of life. 1

Primary Symptoms

• Chronic widespread pain with reduced pain threshold, hyperalgesia (increased pain response), and allodynia (pain from normally non-painful stimuli) 1
• Fatigue that is often debilitating and not relieved by rest 1
• Sleep disturbances including non-restorative sleep 1
• Cognitive dysfunction (often called "fibro fog") affecting memory and concentration 1, 2

Associated Symptoms

• Depression and anxiety 1
• Headaches and migraines 1
• Irritable bowel syndrome with variable bowel habits and diffuse abdominal pain 1
• Urinary frequency 1

Pathophysiology

• Central sensitization is the fundamental mechanism—the central nervous system amplifies pain signals despite no actual tissue damage 3
• Classified as "nociplastic" pain (altered pain processing without tissue damage or nerve injury) 3
• This is NOT a peripheral neuropathy or inflammatory condition 3

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Treatment Algorithm

Optimal management requires starting with non-pharmacological therapies first, adding pharmacological agents only when necessary, and avoiding corticosteroids and strong opioids entirely. 1, 4

Step 1: Initial Non-Pharmacological Management (FIRST-LINE)

Begin with aerobic and strengthening exercise as the primary intervention—this has the strongest evidence (Level Ia, Grade A) for improving pain, function, and quality of life. 4

• Heated pool therapy with or without exercise (Level IIa, Grade B) 1, 4
• Individually tailored exercise programs including aerobic exercise and strength training, gradually increased based on tolerance (Level IIb, Grade C) 1, 4
• Cognitive behavioral therapy (CBT) particularly for patients with concurrent mood disorders or unhelpful coping strategies (Level Ia, Grade A) 4
• Multicomponent therapies combining different approaches show significant benefit (Level Ia, Grade A) 4
• Additional modalities: acupuncture, hydrotherapy, meditative movement therapies (qigong, yoga, tai chi), and mindfulness-based stress reduction (Level Ia, Grade A) 4

Common pitfall: Starting with medications before implementing exercise—this reverses the evidence-based hierarchy and may lead to polypharmacy without addressing the core pathophysiology. 4

Step 2: Add Pharmacological Management (SECOND-LINE)

If insufficient response after 4-6 weeks of non-pharmacological therapy, add one first-line medication based on the predominant symptom profile. 4

First-Line Medications (Level Ia, Grade A)

For patients with prominent sleep disturbances:

• Amitriptyline 10-50 mg at bedtime, increase by 10 mg weekly to target 25-50 mg nightly (Level Ia, Grade A) 1, 4
• Number needed to treat for 50% pain relief: 4.1 4
• Caution: Avoid in older adults (≥65 years) due to anticholinergic effects 4

For patients with comorbid depression or when sedation is undesirable:

• Duloxetine 60 mg once daily (Level Ia, Grade A) 4, 5
• Approximately 50% of patients achieve at least 30% pain reduction 4
• Do NOT escalate to 120 mg/day—no additional benefit but increased adverse events 4, 5

Alternative SNRI:

• Milnacipran 100-200 mg/day in divided doses (Level Ia, Grade A) 1, 4
• Similar efficacy to duloxetine with additional benefits on fatigue 4

For patients with prominent pain and sleep issues:

• Pregabalin 300-450 mg/day (Level Ia, Grade A) 1, 4, 6
• Start low (75 mg twice daily) and titrate over 1 week 6
• Do NOT escalate beyond 450 mg/day—no additional benefit but increased dose-dependent adverse reactions 4, 6
• Adjust dose for creatinine clearance <60 mL/min 4

Second-Line Medication

Tramadol (Level Ib, Grade A) only when first-line medications are ineffective 1, 4

• Use with caution given opioid-related risks 4
• Simple analgesics like paracetamol can be considered but have limited evidence 1

Step 3: Reassess and Adjust

Evaluate treatment efficacy every 4-8 weeks using pain scores, functional status, and patient global impression of change. 4

If partial response:

• Add another first-line medication from a different class 4
• Do NOT combine pregabalin with gabapentin—they bind to identical targets (pharmacologically redundant) 4

If no response at target dosage after adequate trial:

• Switch to an alternative first-line medication from a different class 4

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Critical Medications to AVOID

Never prescribe corticosteroids—they have no demonstrated efficacy in fibromyalgia. 1, 4

Never prescribe strong opioids—they lack benefit and cause significant harm. 1, 4

Do not use NSAIDs as monotherapy—no evidence of improved outcomes compared to placebo. 4

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Common Clinical Pitfalls

• Diagnosing fibromyalgia as a diagnosis of exclusion rather than making a positive clinical diagnosis based on characteristic central sensitization features 3
• Relying solely on pharmacological therapy without implementing exercise and behavioral approaches 4
• Escalating duloxetine beyond 60 mg/day or pregabalin beyond 450 mg/day—this increases adverse events without additional benefit 4, 5
• Failing to provide adequate patient education about the chronic nature of fibromyalgia and central sensitization mechanism 4, 3
• Attributing symptoms to peripheral nerve damage—fibromyalgia is fundamentally a central nervous system disorder 3