Herpes zoster (HZ) is characterized by a painful dermatomal rash and significantly affects quality of life, with acute pain increasing the risk of postherpetic neuralgia. Although early antiviral therapy limits viral replication, its analgesic effect is insufficient, and many patients experience inadequate relief despite stepwise use of non-opioids and opioids. Gabapentinoids such as gabapentin and pregabalin are recommended adjuncts, but their efficacy in acute HZ is inconsistent and often accompanied by adverse effects that limit tolerability. Mirogabalin, a newer gabapentinoid approved for peripheral neuropathic pain, has higher affinity and slower dissociation from the α2δ-1 subunit, suggesting stronger analgesia with fewer central side effects. However, its role in managing acute HZ pain remains unknown. We therefore hypothesize that adding mirogabalin to conventional therapy will provide superior pain relief compared with standard treatment alone, and propose a prospective, randomized, controlled, open-label, blinded-endpoint trial to evaluate this.