Scrambler Therapy in Treating Chronic Pain in Patients With Rash From Varicella Zoster Virus Infection

Inclusion Criteria: * Pain of \>= 1 month (30 days) duration attributed to zoster, for which the patient wants intervention * Pain at least a four out of ten problem during the prior week, on a 0-10 scale where zero was no problem and ten was the worst possible problem * Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) = 0, 1, or 2 * Life expectancy \>= 3 months (90 days) * Ability to complete questionnaire(s) by themselves or with assistance * Provide informed written consent Exclusion Criteria: * Any of the following because this study involves an investigational agent whose genotoxic, mutagenic and teratogenic effects on the developing fetus and newborn are unknown * Pregnant women * Patients with implantable drug delivery systems, e.g. Medtronic Synchromed * Patients with heart stents or metal implants such as pacemakers, automatic defibrillators, aneurysm clips, vena cava clips and skull plates; (metal implants for orthopedic repair, e.g. pins, clips, plates, cages, joint replacements are allowed as are central venous access devices) * Patients with a history of myocardial infarction or ischemic heart disease within the past six months * Patients with history of epilepsy, brain damage, use of anti-convulsants for seizure prevention, symptomatic brain metastases; Note: anti-convulsant use is allowed for neuropathy and heart failure (HF) if on a stable dose * Other identified causes of pain in the area that was affected by herpes zoster * Skin conditions such as open sores that would prevent proper application of the electrodes * Other medical or other condition(s) that in the opinion of the investigators might compromise the objectives of the study * Prior treatment with Calmare MC-5A therapy * Patient initiation of a new analgesic treatment within 7 days prior to initiation of protocol treatment