Postherpetic neuralgia
Neuropathic pain that persists more than 3 months after herpes zoster rash. Patients describe burning, shooting pain and allodynia in the previous lesion area. More common in older adults and after ophthalmic zoster. First line: gabapentinoids and tricyclic antidepressants; localized pain responds to 8% capsaicin (Qutenza) or 5% lidocaine patches.
ICD-10 B02.23 drugs
Also known as: PHN, Pain after shingles
Drugs used for this condition
- ACapsaicinSecond line · Selective TRPV1 agonist, topical analgesic for neuropathic painCapsaicin 8% patch (Qutenza) is an authorised option for postherpetic neuralgia when first-line therapy (gabapentin, pregabalin, amitriptyline) is insufficient. A single 60-minute application reduces pain by about 30% for 8–12 weeks. NICE CG173 and SED (Sociedad Española del Dolor) recommend the patch in localised neuropathic pain and when oral medication is poorly tolerated. The patch is applied by a clinician or trained nurse under local skin anaesthesia.
- AGabapentinFirst line · Gabapentinoids (antiepileptics)First-line for post-herpetic neuralgia. Dose 1800–3600 mg/day. Alternatives: pregabalin, amitriptyline, duloxetine, topical lidocaine and capsaicin. PHN prevention: Shingrix vaccination in adults over 50.
- BFamciclovirAdd-on therapy · Antiviral nucleoside analogue for herpes infections (HSV-1, HSV-2, VZV)Early famciclovir in the first 72 hours of herpes zoster reduces the frequency and duration of postherpetic neuralgia. Fewer patients report pain at 3 and 6 months compared with placebo. Once postherpetic neuralgia is established (pain beyond 3 months after rash), famciclovir does not treat it – neuropathic pain drugs are needed (gabapentin, pregabalin, amitriptyline) or 8% capsaicin and 5% lidocaine patches.
How to read tiers A–F
Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.
- AStrong evidence – first or second line in international guidelines
- BRecommended in selected cases
- CStudy data contradict each other
- DBenefit not proven, no documented harm
- FDocumented harm, or risk without benefit