What is the recommended starting dose of Elavil (amitriptyline) for fibromyalgia?

Starting Dose of Amitriptyline (Elavil) for Fibromyalgia

Start amitriptyline at 10 mg at bedtime and increase by 10 mg weekly to a target dose of 25-50 mg nightly. 1

Dosing Algorithm

Initial Dosing

• Begin with 10 mg at bedtime as the starting dose 1
• This low starting dose minimizes anticholinergic side effects and morning sedation while allowing assessment of tolerability 1

Titration Schedule

• Increase by 10 mg increments weekly based on tolerability and response 1
• The target therapeutic range is 25-50 mg nightly 1
• Some guidelines cite a broader range of 10-75 mg/day, but most patients respond adequately at 25-50 mg 2

Monitoring During Titration

• Watch specifically for anticholinergic effects (dry mouth, constipation, urinary retention) and morning sedation 1
• These side effects occur in approximately 78% of patients on amitriptyline versus 47% on placebo 3
• The number needed to harm for any adverse event is 3.3, meaning one in three patients will experience a side effect attributable to the medication 3

Treatment Context and Expectations

When to Use Amitriptyline

• Amitriptyline should be added as second-line therapy only after non-pharmacological interventions (exercise, cognitive behavioral therapy) have been tried for 4-6 weeks with insufficient relief 1
• It is particularly beneficial for patients with prominent sleep disturbances due to its sedating properties 2

Evidence Quality and Realistic Outcomes

• The evidence supporting amitriptyline is surprisingly weak—there is no first or second tier evidence for its efficacy in fibromyalgia 3
• Using third-tier evidence, the number needed to treat for 50% pain relief is 4.1, meaning only about one in four patients achieves substantial benefit 3
• Despite limited high-quality evidence, amitriptyline remains a first-line pharmacological option based on decades of clinical experience and guideline recommendations 4, 1

Common Pitfalls to Avoid

• Do not start at higher doses (e.g., 25 mg) as this increases early dropout rates due to side effects 1
• Do not use amitriptyline as monotherapy—it must be combined with exercise and behavioral interventions for optimal outcomes 1, 2
• Do not escalate beyond 50 mg in most patients, as higher doses increase side effects without proportional benefit 1
• Do not expect immediate results—therapeutic effects typically emerge over 3-7 weeks 4

Alternative First-Line Medications

If amitriptyline is not tolerated or contraindicated, consider:

• Duloxetine: Start 30 mg daily for 1 week, then increase to 60 mg daily 1
• Pregabalin: Start 75 mg twice daily, increase to 150 mg twice daily within 1 week 1

Both alternatives have stronger evidence (Level Ia, Grade A) compared to amitriptyline's third-tier evidence 4, 1