What is the treatment for brachioradial pruritus?

Treatment for Brachioradial Pruritus

For brachioradial pruritus, a multimodal approach is recommended with gabapentin, pregabalin, or capsaicin cream as first-line treatments based on their effectiveness in reducing neuropathic itch and improving quality of life.

Understanding Brachioradial Pruritus

Brachioradial pruritus (BRP) is a specific type of neuropathic pruritus that primarily affects the dorsolateral aspects of the forearms, particularly over the brachioradialis muscle. It presents with:

• Intense itching, burning, or pain in the affected areas
• Typically bilateral involvement (72% of cases)
• More common in fair-skinned individuals
• Often exacerbated by sun exposure
• Frequently associated with cervical spine pathology

Treatment Algorithm

First-line Treatments:

1. Topical Therapies:

   • Capsaicin cream: Provides significant relief in most patients 1
   • Moderate to high-potency topical steroids: Such as mometasone furoate 0.1% or betamethasone valerate 0.1% ointment 2
   • Menthol 0.5%: May provide counter-irritant effect and soothing relief 2

2. Systemic Medications:

   • Gabapentin (900-3600 mg daily) 2, 3
   • Pregabalin (25-150 mg daily): Shown to be effective in case reports 2, 3, 4
   • Antihistamines:
     • Non-sedating (daytime): Loratadine 10 mg daily
     • Sedating (nighttime): Hydroxyzine 25-50 mg daily 2

Second-line Treatments:

1. Combination therapy:

   • H1 and H2 antagonists together (e.g., fexofenadine and cimetidine) 2

2. Other medications to consider:

   • Amitriptyline or other tricyclic antidepressants 2
   • Aprepitant (NK-1 receptor antagonist) 2
   • Paroxetine, fluvoxamine, or mirtazapine 2

3. Phototherapy:

   • NB-UVB or BB-UVB may provide temporary relief 2

Treatment Considerations

Addressing Underlying Causes:

• Cervical spine evaluation: Since BRP is often associated with cervical radiculopathy (57% of patients in one study showed abnormal F responses diagnostic for cervical radiculopathy) 5
• Sun protection: As UV exposure can trigger or worsen symptoms 1, 4

Important Caveats:

• When using capsaicin cream:

  • Warn patients about initial burning sensation
  • Application normalizes epidermal TRPV1 expression, which may explain its effectiveness 6
  • Does not restore reduced intraepidermal nerve fiber density 6

• When using topical doxepin:

  • Limit treatment to 8 days
  • Apply to no more than 10% of body surface area (maximum 12g daily)
  • Risk of allergic contact dermatitis 2

• Avoid ineffective treatments:

  • Crotamiton cream has not shown significant antipruritic effect 2
  • Calamine lotion is not recommended due to lack of supporting evidence 2

Monitoring and Follow-up

• Reassess after 2 weeks of treatment
• If symptoms worsen or do not improve, escalate to the next treatment option
• For grade 3 (intense, widespread, constant, limiting self-care) or intolerable grade 2 pruritus, consider combination therapy 2

BRP can be challenging to diagnose and treat, with diagnosis often delayed by 2-3 years 4. Early recognition and appropriate treatment can significantly improve quality of life for affected patients.