Herpes zoster is a common disease, usually caused by the reactivation of latent varicella zoster virus from the dorsal root ganglion. Acute herpes zoster is characterized by severe pain and the appearance of vesicular skin rashes that usually heal in 2-3 weeks. One of the complications of acute herpes zoster is post-herpetic neuralgia (PHN), which is usually defined as persistent pain lasing 90 days or more from the onset of skin rash. The reported incidence of PHN ranges from between 5% to over 50%. PHN can negatively impact one's quality of life due to serious physical, psychological, functional, and social disturbances due to consequences of chronic pain. Platelet rich plasma (PRP) is an emerging treatment option for chronic pain. It is currently used predominantly for treating musculoskeletal pain conditions such as osteoarthritis and tendinopathies. However, PRP promotes the healing of nerve injury and reduces neuropathic pain, making it a potentially promising treatment option for neuropathic pain. The effect of interlaminar epidural PRP for PHN has not been studied. In this study, a case series will be performed to investigate the analgesic effect of interlaminar epidural PRP for patients with thoracic herpes zoster.