Postherpetic Neuralgia: A Detailed FAQ

By H. Rand Scott, MD — Medical Director, Newport Pain Management Reviewed and updated July 2026

This is a more detailed, question-and-answer companion to our main shingles and postherpetic neuralgia page, for patients who want the specifics.

What is herpes zoster? "Herpes zoster" is the medical term for shingles — a rash, usually on one side of the body, caused by reactivation of the dormant chicken pox (varicella zoster) virus within specific nerves.

Who gets it? Adults 50–70 account for roughly 40% of cases, and incidence keeps climbing with age after that. It's especially common in people with weakened immunity — certain cancers (it occurs in about a third of patients with Hodgkin's disease), chemotherapy, corticosteroid treatment, and transplant recipients. Many patients report local trauma to the area before onset. It doesn't favor either sex or any season.

Where does it appear? The chest about half the time; the face (trigeminal nerve) 3–20%; the neck and lower back regions 12–20%. It's almost always one-sided. Facial cases become more common with age and carry a higher risk of lasting pain — and can threaten the eye, making them a priority for urgent care.

What is the rash like? Typically a strip of redness followed by pimply eruptions that crust over. Crusting can persist about a month, and the skin can stay red or purplish for a while after. Protect the skin from scratching and extra trauma, wash gently and pat dry, and wash your hands often to avoid spreading infection.

Can it come back? Recurrence happens in roughly 1–8% of patients; about half of those recur in the same location. Vaccination (Shingrix) substantially lowers the risk of both first episodes and recurrence and is the single best preventive step for eligible adults.

What exactly is postherpetic neuralgia? It's defined simply as pain that persists beyond about 4–6 weeks after the shingles outbreak. The pain comes from nerve damage caused by the viral reactivation — a "deafferentation" pain mechanism, in some ways similar to the pain experienced by amputees.

If I get shingles, how likely is PHN? Age is the dominant factor. Defining PHN as pain lasting more than a month after onset, the risk is roughly 16% under age 60 and around 47% over 60.

How long does the pain last? Also strongly age-dependent. The chance of pain persisting beyond a year ranges from very low in younger patients to roughly half in patients over 70. In general, both the frequency and the severity increase with age — the strongest argument for prevention and prompt treatment.

How is acute shingles treated? Antiviral medication (acyclovir, valacyclovir, famciclovir) started as early as possible shortens the course and limits damage. Corticosteroids can speed resolution of the acute pain in selected patients. Sympathetic nerve blocks give relief to 85–90% of patients when done within two weeks of the rash — dropping to about 40% if delayed beyond two weeks — and are especially worth considering in high-risk (older) patients. Pain is controlled with appropriate medications, which for severe acute shingles can include opioids short-term. TENS can help as well.

How is established PHN treated? Long-standing PHN (beyond 3–6 months) is genuinely difficult, and treatment is usually a combination rather than a single fix:

• Nerve-pain medications — gabapentin and pregabalin, and antidepressants such as duloxetine or amitriptyline (amitriptyline has long been among the most useful single agents, though relief is often partial).
• Topical treatments — lidocaine 5% patch, prescription capsaicin.
• Interventional options — early sympathetic blocks for the sharp, lancinating component; spinal cord stimulation for resistant cases.
• Supportive care — physical therapy (exercise reduces pain broadly), psychological support and relaxation techniques, and simple comfort measures like lukewarm baths.
• Adjuncts — selected patients benefit from additional agents chosen case by case.

Neuroablative (nerve-destroying) procedures are generally best avoided, as few have shown durable benefit.

Postherpetic neuralgia is one of the more challenging pain problems, which is exactly why it benefits from a pain specialist's full toolbox. Call Newport Pain Management at (949) 759-8400.

This article is for general education and is not a substitute for individual medical advice.