🔥 Postherpetic Neuralgia Pain Simulator

Acute Rash-Associated Pain in Herpes Zoster

Placeholder: acute dermatomal pain accompanies the shingles rash.

• Days 1–5: Pain onset (Placeholder timing note)
• 5–8/10: Typical VAS score (Placeholder severity note)
• 1–3: Dermatomes affected (Placeholder distribution note)
• 2–4 wks: Rash duration (Placeholder duration note)

Rash and acute neuritis

Placeholder: reactivated virus inflames the nerve and skin together.

Sensory Nerve Fiber Injury Along the Dermatome

Placeholder: viral replication damages sensory axons and ganglia.

• Dorsal root: Ganglion involved (Placeholder location note)
• A-delta, C: Fiber types hit (Placeholder fiber note)
• Age-linked: Damage severity (Placeholder risk note)
• Weeks–months: Recovery window (Placeholder recovery note)

Axonal injury and demyelination

Placeholder: older patients show greater nerve fiber loss.

Aberrant Pain Signal Generation and Central Sensitization

Placeholder: injured fibers generate spontaneous ectopic firing.

• Elevated: Ectopic firing (Placeholder mechanism note)
• Common: Central sensitization (Placeholder spinal note)
• ~30%: Allodynia rate (Placeholder symptom note)
• Irregular: Signal pattern (Placeholder pattern note)

Ectopic firing and spinal amplification

Placeholder: damaged fibers misfire and amplify pain centrally.

Effect of Antiviral Treatment Timing on Pain Outcomes

Placeholder: earlier antiviral therapy reduces nerve damage extent.

• <72 hrs: Ideal start window (Placeholder timing note)
• Worse pain: Delayed start effect (Placeholder outcome note)
• Acyclovir class: Common antivirals (Placeholder drug note)
• Moderate: Benefit magnitude (Placeholder effect note)

Treatment window and nerve protection

Placeholder: fast antiviral start limits viral nerve injury.

Chronic Pain Trajectory Over Months — Resolution or Persistence

Placeholder: pain either fades over months or persists as PHN.

• ~10–20%: PHN at 3 months (Placeholder prevalence note)
• ~5–10%: PHN at 1 year (Placeholder prevalence note)
• Much higher: Older age risk (Placeholder risk note)
• 1–12 months: Typical resolution (Placeholder timeline note)

Long-term pain resolution patterns

Placeholder: trajectory depends on age, severity, and treatment timing.

Placeholder: older patients with delayed treatment face longer chronic pain.