One serious complication associated with shingles — and with the Zostavax vaccine, according to complaints — is post-herpetic neuralgia, or nerve pain and damage caused by the virus.
Patients with post-herpetic neuralgia suffer burning pain, throbbing, extreme sensitivity, itching, and numbness around the area of skin where the shingles outbreak initially occurred. This condition can last long after the shingles blisters clear up, according to Mayo Clinic.
Those who suffer from post-herpetic neuralgia can also develop depression, fatigue, difficulty sleeping, lack of appetite, or difficulty concentrating.