What SSRI (Selective Serotonin Reuptake Inhibitor) can be used to treat itching?

SSRIs for Treatment of Pruritus

Sertraline is the most effective SSRI for treating pruritus, particularly in cholestatic and uremic itch, and should be considered as a third-line treatment option after first-line cholestyramine and second-line rifampicin. 1

Types of Pruritus Responsive to SSRIs

SSRIs work by increasing serotonin concentrations, which can modulate itch perception at both peripheral and central levels. The evidence supports their use in several types of pruritus:

1. Cholestatic Pruritus

   • Sertraline (100 mg daily) is recommended as a third-line treatment 1
   • Has shown significant improvement in pruritus symptoms in patients with primary biliary cirrhosis 2
   • Effective in children with cholestatic pruritus at doses of 1-4 mg/kg/day 3

2. Uremic Pruritus

   • Sertraline has demonstrated effectiveness in end-stage renal disease patients 4
   • Can significantly reduce the severity of pruritus in hemodialysis patients

3. Polycythemia Vera-Associated Pruritus

   • SSRIs are recommended as a treatment option 1
   • Often used when other treatments like aspirin, cytoreductive therapy, or interferon-alpha are ineffective

Treatment Algorithm for Pruritus

1. First-line treatments:

   • Cholestatic pruritus: Cholestyramine (4-16 g/day) 1
   • Uremic pruritus: Gabapentin or nalfurafine 5
   • Polycythemia vera: Aspirin 300 mg daily 1

2. Second-line treatments:

   • Cholestatic pruritus: Rifampicin (300-600 mg/day) 1
   • Uremic pruritus: Naltrexone 5
   • Polycythemia vera: Interferon-alpha, UVB phototherapy 1

3. Third-line treatments:

   • Sertraline (75-100 mg daily) for cholestatic pruritus 1
   • Paroxetine or fluvoxamine for neuropathic pruritus 1
   • Mirtazapine for generalized pruritus of unknown origin 1

Dosing and Administration

• Sertraline: Start at 25-50 mg daily and titrate up to 75-100 mg daily as needed and tolerated
• Paroxetine: Typically 20 mg daily
• Fluvoxamine: Start at 50 mg daily, can increase to 100 mg daily

Monitoring and Side Effects

• Monitor for common SSRI side effects: nausea, headache, insomnia, sexual dysfunction
• Rare but important: Some patients may experience paradoxical worsening of pruritus with SSRIs 6
• Elderly patients may be more sensitive to side effects and should start at lower doses
• Drug interactions should be carefully considered, especially with other serotonergic medications

Special Considerations

• Hepatic impairment: Use caution with sertraline in severe liver disease; may need dose reduction
• Renal impairment: Generally safe but monitor closely
• Pregnancy: Risk-benefit assessment needed; generally category C
• Pediatric use: Sertraline has been used successfully in children with cholestatic pruritus at 1-4 mg/kg/day 3

Treatment Duration

• Initial trial of 4-8 weeks to assess efficacy
• If effective, treatment may be continued long-term as needed
• Periodic attempts at dose reduction or discontinuation may be reasonable in patients with sustained improvement

Limitations and Caveats

• Evidence for SSRI use in pruritus is primarily from small studies and case reports
• Individual response may vary significantly
• May take 2-4 weeks to see maximum benefit due to SSRI mechanism of action
• Not FDA-approved specifically for pruritus treatment

SSRIs represent an important option in the treatment algorithm for pruritus, particularly for patients who have failed first- and second-line therapies. Sertraline has the strongest evidence base among the SSRIs for this indication.