Postherpetic neuralgia (PHN) is a chronic neuropathic pain syndrome that persists for more than three months after the resolution of herpes zoster rash. This condition affects approximately 30% of the population, primarily the elderly and immunocompromised individuals. PHN can be severely debilitating and often proves challenging to treat effectively. Recent advances in prevention and treatment have improved the management of PHN. The introduction of herpes zoster vaccines has shown promise in reducing the incidence of both herpes zoster and PHN. Current treatment guidelines recommend a multimodal approach, with effective therapies including tricyclic antidepressants, topical lidocaine, gabapentin, pregabalin, opioids, and topical capsaicin. This review focuses on optimizing treatment strategies and developing novel therapies to further enhance PHN management.

Acyclovir is effective in treating the herpes virus infection, especially chickenpox and shingles. Hyponatremia caused by acyclovir has been rarely reported. We present a shingles patient with symptomatic hyponatremia that was presumably caused by acyclovir affecting the hypothalamus or posterior pituitary gland. This case demonstrates that the serum electrolyte levels should be checked regularly and careful observation of symptoms such as nausea, convulsions, or mentality change is necessary in patients treated with acyclovir.

Brachial radiculoplexitis is characterized by acute onset of shoulder and arm pain followed by weakness and sensory loss. Brachial radiculoplexitis by herpes zoster is a rare disease, which can be diagnosed by careful history, electrodiagnosis and MRI. It has remained uncertain about clinical characteristics, treatment, and prognosis. Better understanding of this disease helps earlier diagnosis and prompt treatment to minimize neurologic sequale. We present two cases of subacute brachial radiculoplexitis preceded by herpes zoster infection.

The etiology of neuralgia amyotrophy remains unclear. Herpes zoster induced neuralgia amyotrphy has been reported in extremely rare cases. In this case report, we describe the clinical features and electrophysiologic findings in a 68-years-old patient with neuralgia amyotrophy associated with herpes zoster infection. We suggest that brachial plexus inflammation due to viral infection may be a direct cause of reversible neuralgia amyotrophy.

Herpes zoster can involve the variable peripheral nervous system but there have been few reports about plexopathy by the herpes zoster. We report a 54-year-old man with left leg weakness soon after herpes zoster in the left leg. His electrophysiological findings were consistent with the left lower lumbosacral plexopathy. It was concluded that herpeszoster can be considered to be one of the rare causes of the lumbosacral plexopathy.

Shingles is a latent viral infection of the sensory ganglia. It can be accompanied by a variety of neurologic complications,including polyradiculitis and myelitis. A 66-year-old man with diabetes mellitus presented with progressive weakness, hypethesiaand neuralgic pain in his right arm after herpes zoster infection in right C5 dermatome. He was diagnosed with zosterpolyradiculomyelitis and treated with intravenous acyclovir and corticosteroid. It is a rare case of zoster neurologic complication inspite of oral acyclovir treatment.