Rationale:Herpes zoster (HZ) is an infection caused by the varicella-zoster virus reactivation, often leading to peripheral nervous system infection and pain. This case report aimed to present 2 patients with damaged sensory nerves originating from the visceral neurons of the lateral horn of the spinal cord.Patient concerns:Two patients presented intractable, severe lower back pain and abdominal pain, but without rash or herpes. A female patient was admitted 2 months after symptom onset. She was presented with paroxysmal, acupuncture-like pain in the right upper quadrant and around the umbilicus without apparent incentives. A male patient was presented with recurrent episodes of paroxysmal and spastic colic in the left waist and left middle abdomen for 3 days. Abdominal examination showed no tumors or organic lesions in their intra-abdominal tissues or organs.Diagnoses:After excluding organic lesions on the waist and in abdominal organs, patients were diagnosed with herpetic visceral neuralgia without rash.Intervention:The treatment for herpes zoster neuralgia or postherpetic neuralgia was applied for 3 to 4 weeks.Outcome:Antibacterial and anti-inflammatory analgesics were not effective in either patient. The therapeutic effects of herpes zoster neuralgia or postherpetic neuralgia treatment were satisfactory.Lessons:Herpetic visceral neuralgia can be easily misdiagnosed due to the absence of a rash or herpes, resulting in delayed treatment. When patients have severe, intractable pain but no rash or herpes, and the biochemical and imaging examinations are normal, the treatment method for HZ neuralgia can be used. If the treatment is effective, HZ neuralgia is diagnosed. If not, shingles neuralgia can be ruled out. Further investigations are required to elucidate the mechanisms of pathophysiological changes in varicella-zoster virus-induced peripheral HZ neuralgia or visceral neuralgia without herpes.