Preherpetic neuralgia.

We have encountered six zoster patients whose pain preceded rash by 7 to more than 100 days. Pain was severe, burning, and radicular, and located both in dermatomes different from, as well as in, the area of eventual rash. Two patients ultimately developed disseminated zoster with neurologic complications, one of zoster paresis, and the other, a fatal zoster encephalitis; both had been taking long-term, low-dose steroids. A third case of preherpetic neuralgia developed in a patient with prior metastatic carcinoma, and another case in a patient with an earlier episode of brachial neuritis. The final two cases of preherpetic neuralgia developed in individuals with no underlying disease. An extended period of pain before the onset of zoster rash has gone largely unrecognized.