What is the recommended use and dosage of Duloxetine (Selective Norepinephrine Reuptake Inhibitor) for various conditions?

Duloxetine: Recommended Use and Dosage for Various Conditions

Duloxetine is recommended at 60 mg once daily for neuropathic pain, fibromyalgia, and chronic musculoskeletal pain, with an initial dose of 30 mg daily for one week to improve tolerability before increasing to the target dose. 1, 2

Approved Indications and Dosing Recommendations

Neuropathic Pain

• Diabetic Peripheral Neuropathy:
  • Starting dose: 30 mg once daily for 1 week
  • Target dose: 60 mg once daily 1, 2
  • No evidence that doses higher than 60 mg provide additional benefit 2
  • Lower starting doses may be considered for patients with renal impairment 2

Fibromyalgia

• Starting dose: 30 mg once daily for 1 week
• Target dose: 60 mg once daily 2
• No evidence that doses higher than 60 mg provide additional benefit 2, 3

Chronic Musculoskeletal Pain

• Starting dose: 30 mg once daily for 1 week
• Target dose: 60 mg once daily 2
• Indicated for chronic low back pain and osteoarthritis pain 2, 3
• Higher doses do not confer additional benefit 2

Major Depressive Disorder

• Starting dose: 40 mg/day (20 mg twice daily) to 60 mg/day (once daily or 30 mg twice daily)
• Can start at 30 mg once daily for 1 week before increasing to 60 mg once daily
• Maximum effective dose: 60 mg/day (doses up to 120 mg/day studied but no additional benefit) 2

Generalized Anxiety Disorder

• Adults <65 years:
  • Starting dose: 30 mg once daily for 1 week
  • Target dose: 60 mg once daily 2
• Geriatric patients:
  • Starting dose: 30 mg once daily for 2 weeks
  • Target dose: 60 mg once daily 2
• Pediatric patients (7-17 years):
  • Starting dose: 30 mg once daily for 2 weeks
  • Target dose: 30-60 mg once daily 2

Administration Guidelines

• Take orally with or without food
• Swallow capsules whole; do not chew, crush, or open capsules 2
• If a dose is missed, take as soon as remembered unless it's almost time for the next dose 2

Tolerability and Side Effects

• Starting at 30 mg daily for 1 week before increasing to 60 mg significantly reduces the incidence of nausea (16.4% vs 32.9%) 4
• Most common adverse events: nausea, headache, dry mouth, dizziness, and decreased appetite 5
• Most adverse events occur during the first week of treatment and are mild to transient 5, 4
• Discontinuation rate due to adverse events: approximately 15-16% during acute treatment 5, 4

Special Populations

• Renal impairment: Consider lower starting doses and gradual dose increases 2
• Older adults: Use lower starting doses (30 mg daily) and slower titration 1
• Pediatric patients with GAD: Dosing starts at 30 mg daily for 2 weeks before considering an increase 2

Clinical Pearls

• Duloxetine is a selective serotonin and norepinephrine reuptake inhibitor (SSNRI) 3
• Pain relief may begin within one week of treatment at the 60 mg dose 6
• For neuropathic pain, duloxetine (60-120 mg/day) is considered a first-line option along with pregabalin and gabapentin 1
• Avoid combination with CYP1A2 inhibitors or nonselective, irreversible monoamine oxidase inhibitors 6
• Long-term treatment is generally well-tolerated with relatively low discontinuation rates due to adverse events 5

Monitoring

• Regular assessment of pain control, function, and adverse effects is essential 1
• Monitor for somnolence, dizziness, and weight gain during treatment 1
• In patients with diabetes, optimizing glucose control can help prevent or delay neuropathy progression 1