This case series reports novel treatment of three patients with classic brachioradial pruritis (BRP) with valacyclovir resulting in complete, sustained resolution of symptoms.

BRP presents with dorsolateral itching of unclear etiology, though theories have included cervical spine disease or sun exposure.  One study of 111 patients with BRP recommended against routine imaging such as MRI of the cervical spine in this patient population unless there was additional evidence of cervical disease. There are no consistent diagnostic findings with EMG, skin biopsy, and autonomic testing among these patients.   Extensive treatments have been trialed with mixed benefit including conservative approaches with physical therapy, topical creams, and oral medications.  Unfortunately, no treatment has proven consistently effective in clinical trials.

Given the occasional seasonal nature of symptoms, abrupt onset, and poorly elucidated etiology, our series proposed a possible viral etiology for BRP symptoms and assessed efficacy of valacyclovir used off-label in symptomatic management.

A case review of three patients with classic clinical symptoms of BRP who were initiated on valacyclovir off-label for treatment.

Three patients, two woman and one man, in the fifth to seventh decades of life presented with bilateral, classic symptoms of BRP.  None of the patients had other associated neurological symptoms or dermatologic abnormalities beyond modest skin excoriations associated with scratching.  Two of the three patients have trialed topical treatments without improvement and one had been prescribed oral medications without resolution.  After clinical diagnosis of BRP, the three patients were initiated on 2 weeks of valacyclovir with subsequent complete resolution of symptoms without recurrence, up to 5 years later.

This case series suggests an alternative mechanism for BRP involving an underlying herpetic condition, supported by completed and sustained resolution of symptoms with 2 weeks of initiation of valacyclovir.  Further studies assessing the origin and therapy of this mysterious disorder are warranted.