What medications are used to treat itching?

Medications for Itching

For itching (pruritus), first-line treatment includes topical corticosteroids for mild-to-moderate cases, non-sedating antihistamines for daytime use, and sedating antihistamines for nighttime relief, with antiepileptic agents like gabapentin or pregabalin reserved for refractory cases. 1, 2

Topical Treatments

• Apply emollients regularly to prevent and treat skin dryness, which is a common contributor to pruritus 1, 2
• For mild to moderate localized pruritus, use moderate-potency topical corticosteroids such as:
  • Mometasone furoate 0.1% ointment 1
  • Betamethasone valerate 0.1% ointment 1
  • Hydrocortisone 1% cream (available over-the-counter) for mild cases 3
• Topical corticosteroids should be applied to affected areas no more than 3-4 times daily 3
• Topical menthol 0.5% preparations can provide additional soothing effects 1
• Lotions containing urea or polidocanol may also help relieve itching 1
• Avoid long-term use of topical corticosteroids (>2-4 weeks) due to risk of skin atrophy 4

Systemic Antihistamines

• For daytime use, non-sedating second-generation antihistamines are recommended:
  • Loratadine 10 mg daily 1, 2
  • Fexofenadine 180 mg daily 2
• For nighttime use, first-generation antihistamines with sedative properties can be beneficial:
  • Diphenhydramine 25-50 mg daily 1
  • Hydroxyzine 25-50 mg daily 1, 5
• Sedative antihistamines should be used with caution, especially in elderly patients, due to risk of cognitive impairment 2, 4
• Antihistamines are particularly effective for histamine-mediated pruritus (like urticaria) but may also help break the itch-scratch cycle in other conditions 6

Treatment for Refractory Pruritus

• Antiepileptic agents can be used as second-line treatment for pruritus that fails to respond to antihistamines:
  • Gabapentin (900-3600 mg daily) 1, 2
  • Pregabalin (25-150 mg daily) 1, 2
• Pregabalin reduces pruritus at the peripheral level by decreasing calcitonin gene-related peptide release and at the central level through modulation of μ-opioid receptors 1
• Tricyclic antidepressant doxepin (a potent histamine antagonist) can be used in both topical and oral preparations 1, 2
• Other antidepressants that may help with pruritus include:
  • Paroxetine 2, 7
  • Sertraline 2, 7
  • Mirtazapine 7

Special Considerations for Specific Causes

• For opioid-induced pruritus, naltrexone is recommended if cessation of opioid therapy is not possible 2
• For hepatic pruritus, rifampicin is considered first-line treatment, with cholestyramine as second-line 2
• For uremic pruritus, ensure adequate dialysis and normalize calcium-phosphate balance; capsaicin cream, topical calcipotriol, or oral gabapentin may be beneficial 2

Treatment Algorithm Based on Severity

1. Mild localized pruritus:

   • Emollients + topical corticosteroids 1, 3
   • Consider topical menthol preparations 1

2. Moderate pruritus:

   • Continue topical treatments
   • Add non-sedating antihistamines for daytime and sedating antihistamines for nighttime 1

3. Severe or widespread pruritus:

   • Continue above treatments
   • Consider antiepileptic agents (gabapentin/pregabalin) 1
   • For temporary relief of particularly severe pruritus, systemic corticosteroids (0.5-2 mg/kg daily) may be used 1

4. Refractory pruritus:

   • Consider tricyclic antidepressants or other antidepressants 1, 2, 7
   • Evaluate for underlying systemic conditions 2

Common Pitfalls and Caveats

• Topical antihistamines should be avoided due to increased risk of contact dermatitis 1
• Long-term use of sedative antihistamines should be avoided except in palliative care 2
• Gabapentin should not be used in hepatic pruritus despite its efficacy in other forms of pruritus 2
• If no improvement after 2 weeks of appropriate therapy, reassess diagnosis 4
• Always treat the underlying cause of pruritus when identified 1, 2