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Postherpetic neuralgia — Clinical Guidelines

Overview

Postherpetic neuralgia (PHN) is a chronic neuropathic pain condition that develops following an episode of herpes zoster (shingles), typically persisting beyond one month post-infection 1 2.

Diagnosis

Persistent pain lasting more than 3 months after herpes zoster rash 2.

Characteristic neuropathic pain features, including allodynia and hyperalgesia 2.

No specific diagnostic tests; clinical evaluation and patient history are crucial 2.

Management

First-line treatments:

- Antidepressants (e.g., tricyclic antidepressants like amitriptyline) 2 9. - Antiepileptic drugs (e.g., gabapentin, pregabalin) 2 9. - Topical agents (e.g., lidocaine patches) 4 8 12.

Adjunctive treatments:

- Opioid analgesics for severe pain 9. - Pulsed radiofrequency (PRF) and temporary spinal cord stimulation (SCS) for refractory cases 1. - Capsaicin topical patches 5. - Surgical interventions like skin excision for localized, severe pain 10.

Special Populations

Elderly: PHN is more prevalent and challenging to manage in older adults 2 9.

Comorbidities: Management considerations for patients with chronic renal failure may include dose adjustments for certain medications 7.

Key Recommendations

Initiate first-line pharmacological treatments with tricyclic antidepressants or anticonvulsants early in the management of PHN (Evidence: Strong 2 9).

Consider topical lidocaine patches as an effective adjunctive therapy for PHN, supported by randomized controlled trials (Evidence: Strong 8 12).

Explore interventional therapies such as pulsed radiofrequency or temporary SCS for patients with refractory PHN symptoms (Evidence: Moderate 1).

Evaluate surgical options like skin excision for patients with localized, severe PHN unresponsive to conservative treatments (Evidence: Weak 10).

Tailor treatment plans considering patient comorbidities, particularly in elderly or those with chronic renal failure (Evidence: Expert opinion).

References

1 Abbas A, Sabet H, El-Moslemani M, Abo-Elnour DE, Olama SM, Saleh MGA et al.. From Short-Term Relief to Long-Term Management: A Meta-Analysis of Temporary Spinal Cord Stimulation and Pulsed Radiofrequency in Postherpetic Neuralgia. Neuromodulation : journal of the International Neuromodulation Society 2025. link 2 Gónima Valero E, Mendoza WAS, Sarmiento DA, Amaya S. Analgesic Treatment Approach for Postherpetic Neuralgia: A Narrative Review. Journal of pain & palliative care pharmacotherapy 2023. link 3 Dey S, Khetarpal M. Re: evaluation of the efficacy of erector spinae plane block and intercostal nerve block in the postherpetic neuralgia. Agri : Agri (Algoloji) Dernegi'nin Yayin organidir = The journal of the Turkish Society of Algology 2021. link 4 Khaliq W, Alam S, Puri NK. WITHDRAWN: Topical lidocaine for the treatment of postherpetic neuralgia. The Cochrane database of systematic reviews 2013. link 5 Sayanlar J, Guleyupoglu N, Portenoy R, Ashina S. Trigeminal postherpetic neuralgia responsive to treatment with capsaicin 8 % topical patch: a case report. The journal of headache and pain 2012. link 6 Franz M, Spohn D, Ritter A, Rolke R, Miltner WHR, Weiss T. Laser heat stimulation of tiny skin areas adds valuable information to quantitative sensory testing in postherpetic neuralgia. Pain 2012. link 7 Semionov V, Shvartzman P. Post herpetic itching--a treatment dilemma. The Clinical journal of pain 2008. link 8 Khaliq W, Alam S, Puri N. Topical lidocaine for the treatment of postherpetic neuralgia. The Cochrane database of systematic reviews 2007. link 9 Pappagallo M, Haldey EJ. Pharmacological management of postherpetic neuralgia. CNS drugs 2003. link 10 Petersen KL, Rice FL, Suess F, Berro M, Rowbotham MC. Relief of post-herpetic neuralgia by surgical removal of painful skin. Pain 2002. link00029-5) 11 Jacob PC, Chand RP, Omeima el-S. Asterixis induced by gabapentin. Clinical neuropharmacology 2000. link 12 Galer BS, Rowbotham MC, Perander J, Friedman E. Topical lidocaine patch relieves postherpetic neuralgia more effectively than a vehicle topical patch: results of an enriched enrollment study. Pain 1999. link00244-9) 13 Rowbotham MC, Reisner-Keller LA, Fields HL. Both intravenous lidocaine and morphine reduce the pain of postherpetic neuralgia. Neurology 1991. link 14 Jones MJ, Murrin KR. Intercostal block with cryotherapy. Annals of the Royal College of Surgeons of England 1987. link

Postherpetic neuralgia