Herpes zoster may produce two painful conditions: acute herpes zoster, known as shingles, or post-herpetic neuralgia.
Acute herpes zoster is an outbreak of rash due to shingles does occur abruptly without a known cause. In some cases, it is associated with an infection or a malignancy or an immunosuppressed state. The herpetic virus remains dormant in nerve root ganglion and then spreads along the sensory nerves, where the lesions erupt on the skin. The lesion may be distributed to the thoracic or lumbar nerves or ophthalmic division of Trigeminal nerve.
Patient experiences severe, excruciating, burning pain along the distribution of sensory nerves. The pain occurs sometimes before the eruptions of the shingles.