Fibromyalgia: Symptoms and Treatment
Core Clinical Symptoms
Fibromyalgia is characterized by chronic widespread pain with reduced pain threshold (hyperalgesia and allodynia), accompanied by a constellation of associated symptoms that significantly impair quality of life. 1
Primary Symptom Domains
- Chronic widespread pain affecting all four quadrants of the body for at least 3 months, with pain on palpation in at least 11 of 18 specific tender points 1, 2
- Fatigue that is persistent and debilitating 1
- Sleep disturbances including difficulty with initiation, maintenance, and non-restorative sleep 1
- Cognitive dysfunction ("fibro fog") affecting concentration, attention, memory, and processing speed 1, 3
Associated Symptoms
- Mood disturbances including depression and anxiety 1
- Headache and migraine 1
- Stiffness in muscles and joints 3
- Variable bowel habits and diffuse abdominal pain 1
- Urinary frequency 1
Pathophysiology
The underlying mechanism is central sensitization where the central nervous system amplifies pain signals despite no evidence of actual tissue damage, classified as "nociplastic" pain distinct from neuropathic or inflammatory pain 4. This involves peripheral and central hyperexcitability at spinal or brainstem level with altered pain perception 1.
Treatment Algorithm
Step 1: Non-Pharmacological Management (First-Line)
Begin immediately with patient education about central sensitization followed by a graduated exercise program—this is the foundation of treatment with the strongest evidence (Level Ia, Grade A). 5, 2
Exercise Protocol
- Start with low-intensity aerobic exercise: 10-15 minutes of walking, swimming, or cycling, 2-3 times weekly 2
- Gradually increase intensity based on tolerance to avoid symptom flare-ups 5
- Add strength training as tolerated, creating an individually tailored program 5
- Heated pool therapy with or without exercise is highly effective (Level IIa, Grade B) 5
Cognitive Behavioral Therapy
- Prioritize CBT for patients with mood disorders (depression, anxiety) or maladaptive coping strategies, as this subgroup shows the strongest benefit (Level IV, Grade D) 5, 2
Additional Supportive Therapies
- Acupuncture and hydrotherapy provide relief for many patients (Level Ia, Grade A) 5
- Meditative movement therapies (qigong, yoga, tai chi) and mindfulness-based stress reduction improve symptoms and quality of life (Level Ia, Grade A) 5
- Multicomponent therapies combining different approaches show significant benefit (Level Ia, Grade A) 5
Reassessment Timeline
- Evaluate response after 4-6 weeks using pain scores, functional status, and patient global impression of change 5, 2
Step 2: Pharmacological Management (Second-Line)
If non-pharmacological interventions provide insufficient relief after 4-6 weeks, add one of three first-line medications: amitriptyline, duloxetine, or pregabalin. 5, 2
Amitriptyline (Level Ia, Grade A)
- Dosing: Start 10 mg at bedtime, increase by 10 mg weekly to target 25-50 mg nightly (maximum 75 mg/day) 5, 2
- Benefits: Pain reduction, improved function, particularly beneficial for sleep disturbances due to sedating properties 5
- Number needed to treat: 4.1 for 50% pain relief 2
- Therapeutic effects: Emerge over 3-7 weeks 2
- Caution: Avoid in older adults (≥65 years) due to anticholinergic effects; monitor for morning sedation 5, 2
Duloxetine (Level Ia, Grade A)
- Dosing: Start 30 mg once daily for 1 week, then increase to 60 mg once daily 5, 2
- Benefits: Pain reduction, functional improvement, treats comorbid depression 5
- Important: Do NOT escalate beyond 60 mg/day—no additional benefit but increased adverse events 5
- Efficacy: Approximately 50% of patients achieve at least 30% pain reduction 5
Pregabalin (Level Ia, Grade A)
- Dosing: Start 75 mg twice daily, increase to 150 mg twice daily within 1 week based on tolerance (target 300-450 mg/day) 5, 2, 6
- Benefits: Pain reduction, sleep improvement, FDA-approved for fibromyalgia 5, 6
- Important: Do NOT escalate beyond 450 mg/day—no additional benefit but increased dose-dependent adverse reactions 5, 6
- Renal adjustment: Required for creatinine clearance <60 mL/min 5
- Onset: Some patients experience pain decrease as early as Week 1 6
Alternative First-Line Options
Milnacipran (Level Ia, Grade A)
- Dosing: 100-200 mg/day in divided doses, with dose escalation over approximately 1 week 5
- Benefits: Pain reduction, fatigue improvement 5
- Dropout rate: Approximately double compared to placebo due to side effects 5
Cyclobenzaprine (Level Ia, Grade A)
- Can be considered for pain management 5
Step 3: Second-Line Pharmacological Options
Tramadol (Level Ib, Grade A)
- Use only when first-line medications are ineffective 5
- Caution: Use with caution given opioid-related risks 5, 2
Gabapentin (off-label)
- Not FDA-approved for fibromyalgia but shares similar mechanism to pregabalin 5
- Efficacy: 49% of patients achieved ≥30% pain reduction vs. 31% with placebo 2
- Requires careful titration due to nonlinear pharmacokinetics (saturable absorption) 5
- Side effects: Somnolence, dizziness, weight gain; 16% discontinue due to adverse events 2
Critical Medications to AVOID
Never prescribe corticosteroids or strong opioids for fibromyalgia—they lack efficacy and cause significant harm. 5, 2
- Corticosteroids: No efficacy demonstrated (Level Ia, Grade A) 5
- Strong opioids: No benefit with significant harm (Level Ia, Grade A) 5, 2
- NSAIDs as monotherapy: No evidence of improved outcome compared with placebo 5
Treatment Combination Strategy
If partial pain relief is achieved with one first-line medication, consider adding another first-line medication from a different class (e.g., duloxetine + pregabalin). 5
Do NOT combine gabapentin with pregabalin—they bind to identical targets with the same mechanism, making this combination pharmacologically redundant. 5
Multicomponent therapy combining exercise, CBT, and medication may provide greater benefit than any single intervention. 5
Common Pitfalls to Avoid
- Relying solely on pharmacological therapy without implementing exercise and behavioral approaches—non-pharmacological interventions have the strongest evidence and must be first-line 5
- Not providing adequate patient education about central sensitization and the chronic nature of fibromyalgia—this is crucial for setting realistic expectations 5, 2
- Diagnosing fibromyalgia as a diagnosis of exclusion rather than as a positive clinical diagnosis based on characteristic features 4
- Escalating duloxetine beyond 60 mg/day or pregabalin beyond 450 mg/day—no additional benefit but increased adverse events 5
- Expecting dramatic improvement—effect sizes for most treatments are modest, with small to moderate benefits 5
- Not reassessing regularly—evaluate treatment efficacy every 4-8 weeks and adjust as needed 5
Monitoring and Reassessment
Regular reassessment every 4-8 weeks is essential using: 5
- Pain scores (visual analog scale)
- Functional status (Fibromyalgia Impact Questionnaire)
- Patient global impression of change
- Side effects monitoring
If no or inadequate pain relief occurs at target dosage after an adequate trial, switch to an alternative first-line medication. 5