What are the treatment options for pruritus (itching)?

Treatment Options for Pruritus (Itching)

For generalized pruritus of unknown origin (GPUO), first-line treatment should include self-care advice, emollients, and topical therapies such as moderate-potency topical corticosteroids or menthol-containing preparations. 1

Initial Assessment and Treatment Algorithm

Step 1: Identify the Type of Pruritus

• Inflammatory (e.g., eczema, psoriasis, dermatitis)
• Neuropathic (e.g., postherpetic neuralgia)
• Systemic disease-related (e.g., hepatic, renal, hematologic)
• Drug-induced (e.g., opioid, chloroquine)
• Unknown origin

Step 2: First-Line Topical Treatments

For All Types of Pruritus:

• Emollients and moisturizers - Apply regularly to maintain skin barrier 1
• Topical corticosteroids - For inflammatory causes:
  • Hydrocortisone 2.5% for mild cases 2, 3
  • Mometasone furoate 0.1% or betamethasone valerate 0.1% for moderate cases 1
  • Apply to affected areas up to 3-4 times daily 2

For Mild-to-Moderate Pruritus:

• Menthol-containing preparations (0.5%) - Provides cooling sensation 1
• Topical doxepin - Limited to 8 days, 10% of body surface area, and 12g daily 1

Step 3: Systemic Treatments

First-Line Systemic Options:

• Non-sedating antihistamines for daytime use:
  • Loratadine 10mg daily
  • Fexofenadine 180mg daily 1

Second-Line Systemic Options:

• Sedating antihistamines for nighttime use:
  • Hydroxyzine 25-50mg daily 1, 4
  • Cetirizine 10mg daily 1

For Refractory Cases:

• Combination H1 and H2 antagonists (e.g., fexofenadine and cimetidine) 1
• Antiepileptic agents:
  • Gabapentin (900-3600mg daily)
  • Pregabalin (25-150mg daily) 1, 3
• Other agents based on specific causes:
  • Paroxetine, mirtazapine, or naltrexone for GPUO 1
  • Rifampicin as first-line for hepatic pruritus 1

Specific Treatment Approaches by Cause

For Inflammatory Pruritus (60% of cases) 3:

• Topical anti-inflammatory therapies
• Consider referral to dermatology for systemic treatments if topical therapies fail

For Neuropathic Pruritus (25% of cases) 3:

• Topical agents: menthol, pramoxine, or lidocaine
• Gabapentin or pregabalin
• Referral to relevant specialist 1

For Drug-Induced Pruritus:

• Opioid-induced: Naltrexone (first choice) or methylnaltrexone 1
• Postoperative: Diclofenac 100mg rectally 1
• Chloroquine-induced: Prednisolone 10mg, niacin 50mg, or combination 1

For Hepatic Pruritus:

1. Rifampicin (first-line) 1
2. Cholestyramine (second-line) 1
3. Sertraline (third-line) 1
4. Naltrexone or nalmefene (fourth-line) 1
5. Consider other options for refractory cases 1

Important Caveats and Pitfalls

• Avoid crotamiton cream for GPUO (Strength of recommendation B) 1
• Avoid topical capsaicin or calamine lotion for GPUO 1
• Do not use gabapentin in hepatic pruritus 1
• Limit sedating antihistamines to short-term use except in palliative care, as long-term use may predispose to dementia 1
• Recognize that antihistamines are most effective for histamine-mediated pruritus (e.g., urticaria) but may be less effective for other causes 5
• Consider referral to secondary care if there is diagnostic doubt or if primary care management does not relieve symptoms 1

Remember that pruritus can significantly impact quality of life and may be a symptom of serious underlying disease. Treatment should address both symptom relief and the underlying cause when identified.