Role of low-level laser therapy in post-herpetic neuralgia: a pilot study

Lasers Med Sci. 2020 Oct;35(8):1759-1764. doi: 10.1007/s10103-020-02969-5. Epub 2020 Jan 31.


The aim of the present study was to investigate the influence of low-level laser radiation at a wavelength of 650 nm for treating post-herpetic neuralgia, an extremely painful condition which frequently occurs severely in old age and may persist for years with no predictable course. In total, fifteen patients were included in the present study, out of which 8 were females and 7 were males aged between 42 and 82 years. All patients were treated through 16 sessions for 8 weeks, and pain scoring was done on a visual analogue scale and statistical analysis was made for comparison before and after treatments. The final pain score was 0 in 11 patients although their initial pain score was severe in 8 and moderate in 3 patients. In three patients, pain reduced to mild intensity (2-3), and in one, the final pain score was 4 on the visual analogue scale. Patients treated during the present study have not complained for recurrence of pain or any other abnormality even after many months since completion of the therapy. Overall, low-level laser therapy (LLLT) proved itself an excellent therapeutic modality for the relief of pain in post-herpetic neuralgia patients, which may replace pain management medicines in future.

Keywords: Laser diode at 650 nm; Low-level laser therapy (LLLT); Pain relief; Photobiomodulation; Post-herpetic neuralgia (PHN); Visual analogue scale.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Humans
  • Low-Level Light Therapy*
  • Male
  • Middle Aged
  • Neuralgia, Postherpetic / complications
  • Neuralgia, Postherpetic / radiotherapy*
  • Pain / complications
  • Pilot Projects
  • Visual Analog Scale