Hi, You need to do work up for any condition which can decrease bodies immunity. Ideally sugar levels and HIV should also be tested. Chest X-ray may also be done. Usually, immunocompromised patients tend to have recurrent herpes. Also get it examined by a dermatologist as whether it s new infection or a condition related to older one and called post herpatic neuralgia. Decision should be made whether Acyclovir may be started or only supportive treatment may be given. Topical application as well as oral analgesics like acetaminophen or Ibuprofen can be helpful. For severe Pain more potent analgesic like Tramadol or Gabapentin may be needed. Hope I have answered your question. Let me know if I can assist you further. Wishing you a speedy recovery. Regards, Dr. Saddiq Ulabidin, General & Family Physician