Post-herpetic neuralgia is the pain that occurs after the post-sheng neuropathic pain has spread to the zona pectoris where the rash has passed. Shingles are generally seen in elderly patients, and may also be seen in young patients, particularly those with cancer, in immunocompromised patients. Zona actually occurs when varicella-zoster virus, which causes waterborne virus in our childhood, becomes active in the spinal cord many years after its placement in the nerve roots. This can trigger immunosuppression, stress, and a rash of illness called zona. The rash usually covers the skin on one side of the body and gives a certain nervous sensation, most commonly seen in the chest area, also on the head, neck, face and legs.