What is the recommended dose of duloxetine (Cymbalta) for treating major depressive disorder, generalized anxiety disorder, or neuropathic pain?

Duloxetine Dosing Recommendations for Various Indications

Duloxetine is recommended at specific dosages depending on the condition being treated. For major depressive disorder (MDD), the recommended dose is 60 mg once daily, with no evidence that doses greater than 60 mg/day confer additional benefits, though doses up to 120 mg/day have been studied and may be considered in certain cases. 1

Dosing by Indication

Major Depressive Disorder

• Starting dose: 40-60 mg/day (given as 20 mg twice daily or 60 mg once daily)
• For some patients, starting at 30 mg once daily for 1 week may help adjustment
• Target dose: 60 mg once daily
• Maximum dose: 120 mg/day (though no additional benefit over 60 mg/day has been demonstrated) 1

Generalized Anxiety Disorder

• Adults <65 years: 60 mg once daily
• Some patients may start at 30 mg once daily for 1 week to adjust
• Geriatric patients: Start at 30 mg once daily for 2 weeks before considering increase to 60 mg/day
• Pediatric patients (7-17 years): Start at 30 mg once daily for 2 weeks before considering increase to 60 mg/day
• Dose range: 30-60 mg once daily (some patients may benefit from doses up to 120 mg/day) 1, 2

Diabetic Peripheral Neuropathic Pain

• Recommended dose: 60 mg once daily
• No evidence that higher doses confer additional significant benefit
• Lower starting dose may be considered for patients with tolerability concerns
• For patients with renal impairment, consider lower starting dose with gradual increase 3, 1, 4

Fibromyalgia

• Start at 30 mg once daily for 1 week
• Target dose: 60 mg once daily
• No evidence that doses greater than 60 mg/day confer additional benefit 1, 4

Chronic Musculoskeletal Pain (Osteoarthritis/Low Back Pain)

• Recommended dose: 60 mg once daily 4

Dose Adjustments for Special Populations

Renal Impairment

Dose adjustment based on creatinine clearance:

• ≥60 mL/min: 300-600 mg/day
• 30-59 mL/min: 150-300 mg/day
• 15-29 mL/min: 75-150 mg/day
• <15 mL/min: 25-75 mg/day 3

Administration Guidelines

• Take orally with or without food
• Swallow capsules whole - do not chew, crush, or open capsules
• If a dose is missed, take as soon as remembered unless it's almost time for the next dose 1

Important Clinical Considerations

Efficacy Considerations

• For neuropathic pain, duloxetine has shown positive results with doses of 20-120 mg/day with "strong recommendations for use" 5
• While 120 mg/day has been studied and shown to be effective, there is no evidence that doses greater than 60 mg/day provide additional benefits for most indications 1, 6

Tolerability and Side Effects

• Most common side effects: nausea, dry mouth, headache, constipation, dizziness, and fatigue 5, 2
• Most adverse events are mild to moderate and occur during initial treatment 6, 7
• Rapid dose escalation (60 mg → 90 mg → 120 mg) has been shown to be safe and tolerable 6

Common Pitfalls to Avoid

• Abrupt discontinuation should be avoided - gradual tapering is recommended to prevent withdrawal symptoms
• Duloxetine is contraindicated in patients with severe hepatic and renal impairment 5
• Concomitant use with potent CYP1A2 inhibitors should be avoided
• Use with caution in patients receiving drugs extensively metabolized by CYP2D6 1

By following these dosing recommendations and considering patient-specific factors, duloxetine can be effectively used to treat various conditions including MDD, GAD, and neuropathic pain with optimal therapeutic outcomes.