Vasculitic mononeuritis multiplex induced by valacyclovir

Abstract

Side effects of antiviral drugs used for management of herpes labialis and other infections include systemic and cutaneous vasculitis and worsening of vasculitic peripheral neuropathies. Isolated peripheral nervous system vasculitis is not a recognized adverse effect. We describe a woman who developed mononeuritis multiplex after treatment of herpes labialis with valacyclovir. A 27-year-old woman with uncomplicated recurrent episodes of herpes labialis since 10 years of age was treated for the first time with oral valacyclovir, 2,000 mg twice daily. One week later, she developed paresthesias over the lateral aspect of her left foot, followed by paresthesias in the right toes. She subsequently developed right ulnar nerve distribution hypoesthesia and weakness of right finger abduction accompanied by severe pain. She was evaluated 2 weeks after symptom onset. There was atrophy of first dorsal interosseous and weakness of all ulnar innervated muscles of her right hand. Deep …