What medications can be used to treat itching and scratching?

Medications for Treating Itching and Scratching

For most cases of itching and scratching, a stepwise approach starting with topical treatments like hydrocortisone 1% cream and progressing to oral antihistamines is recommended, with more specialized treatments for refractory cases. 1

First-Line Treatments

Topical Treatments

• Topical corticosteroids:

  • Mild-to-moderate potency: Hydrocortisone 1% cream for facial application and sensitive areas 2
  • Moderate potency: Mometasone furoate 0.1% ointment or betamethasone valerate 0.1% ointment for body 1
  • Apply twice daily for 1-2 weeks

• Other topical agents:

  • Menthol 0.5% containing preparations 1
  • Lotions containing urea or polidocanol 1
  • Avoid crotamiton cream (not effective) 1
  • Avoid topical capsaicin or calamine lotion (not recommended for generalized pruritus) 1

Oral Antihistamines

• Daytime use (non-sedating):

  • Loratadine 10 mg daily 1
  • Fexofenadine 180 mg daily 1
  • Cetirizine 10 mg daily (mildly sedating) 1

• Nighttime use (sedating):

  • Diphenhydramine 25-50 mg every 6 hours 1
  • Hydroxyzine 25-50 mg at bedtime 1
  • Promethazine 12.5-25 mg every 6 hours 1

Warning: Avoid long-term use of sedating antihistamines, especially in elderly patients, as they may predispose to dementia 3

Second-Line Treatments

For Persistent Pruritus

• Antiepileptic agents:
  • Gabapentin (900-3600 mg daily) 1
  • Pregabalin (25-150 mg daily) 1

For Specific Causes

• Opioid-induced pruritus:
  • Naltrexone (first choice if opioid therapy cannot be stopped) 1
  • Nalbuphine 0.5-1 mg IV every 6 hours as needed 1
  • Consider naloxone infusion 0.25 mcg/kg/h and titrate up for relief without decreasing analgesia 1

Treatment Algorithm Based on Severity

Mild Localized Itching

1. Start with topical hydrocortisone 1% cream twice daily
2. Add non-sedating antihistamine if needed
3. Consider topical menthol preparations

Moderate Generalized Itching

1. Higher potency topical corticosteroids for body areas
2. Non-sedating antihistamine during day
3. Sedating antihistamine at night if sleep is affected
4. Consider combination of H1 and H2 antagonists (e.g., fexofenadine and cimetidine) 1

Severe or Refractory Itching

1. Consider gabapentin or pregabalin
2. Consider referral to dermatology if no improvement after 2 weeks 1, 3
3. For specific conditions:
   • Consider aprepitant for anticancer drug-induced pruritus 1
   • Consider doxepin (tricyclic antidepressant) for general pruritus 1

Special Considerations

Elderly Patients

• Avoid sedating antihistamines except in palliative care settings 1
• Consider gabapentin as it may be particularly useful 1
• Use moisturizers with high lipid content 1

Cancer Patients

• Assess for other causes of pruritus (medications, cholestasis, etc.) 1
• Consider changing opioid if pruritus persists despite treatment 1
• For anticancer therapy-related pruritus, treatment should continue while managing symptoms 1

Common Pitfalls to Avoid

1. Using sedating antihistamines long-term, especially in elderly patients
2. Failing to identify and treat underlying causes
3. Using topical diphenhydramine, which can be absorbed systemically and cause toxicity 4
4. Overlooking pruritus as a potential sign of serious conditions like bullous pemphigoid 3
5. Continuing ineffective treatments beyond 2 weeks without reassessment

Remember that persistent or severe itching warrants investigation for underlying systemic causes, including malignancy, liver disease, kidney disease, or drug reactions 5.