Treatment of Shingles Pain
For acute shingles pain, initiate oral antiviral therapy with famciclovir 500 mg three times daily for 7 days, valacyclovir 1000 mg three times daily for 7 days, or acyclovir 800 mg five times daily for 7-10 days, starting as soon as possible and ideally within 72 hours of rash onset. 1, 2, 3
Antiviral Therapy Selection
First-line options include:
- Famciclovir 500 mg orally three times daily for 7 days - FDA-approved with the most convenient dosing and proven to reduce postherpetic neuralgia duration by 3.5 months in patients ≥50 years old 1, 4
- Valacyclovir 1000 mg orally three times daily for 7 days - equivalent efficacy to famciclovir with three-times-daily dosing 3, 5
- Acyclovir 800 mg orally five times daily for 7-10 days - effective but requires more frequent dosing which may reduce compliance 6, 2, 3
Key consideration: Famciclovir and valacyclovir have superior dosing convenience (three times daily) compared to acyclovir (five times daily), which improves adherence 3. All three agents shorten viral shedding, accelerate rash healing by 1-2 days, and reduce acute pain intensity and duration 3, 5.
Timing of Treatment Initiation
- Initiate therapy within 72 hours of rash onset for maximum benefit 1, 2
- Treatment started after 72 hours may still provide benefit for pain reduction, though evidence is less robust 5
- Begin at the first sign of prodromal symptoms (burning, pain) or rash appearance 1
Pain Management During Acute Phase
Acute neuritic pain (lasting 2-8 weeks):
- Antiviral therapy itself reduces acute pain intensity and duration 3, 7
- Consider adding oral corticosteroids (prednisolone 40 mg daily, tapered over 3 weeks) for modest additional pain relief during the acute phase, though this does NOT reduce postherpetic neuralgia risk 7
- Analgesics tailored to pain severity: NSAIDs for mild pain, opioids for moderate-to-severe pain 2
Important caveat: While corticosteroids provide slightly greater pain reduction on days 7-14 of acute infection, they do not prevent postherpetic neuralgia and are associated with more adverse events 7. Use selectively in patients with severe acute pain.
Special Populations
Immunocompromised patients:
- Require more aggressive management with higher doses 6
- For severe cases: intravenous acyclovir 5 mg/kg every 8 hours 6
- Monitor closely for treatment failure and consider extended therapy 6
Patients with renal impairment:
- Dose reduction is mandatory to prevent acute renal failure 1
- For famciclovir: adjust based on creatinine clearance (e.g., CrCl 20-39 mL/min: 500 mg every 24 hours; CrCl <20 mL/min: 250 mg every 24 hours) 1
Postherpetic Neuralgia Management
If pain persists beyond 8 weeks (postherpetic neuralgia):
- Tricyclic antidepressants in low doses for neuropathic pain control 2
- Anticonvulsants (gabapentin, pregabalin) for neuropathic pain 2
- Topical lidocaine patches for localized pain 2
- Topical capsaicin in selected patients 2
- Opioids may be required for adequate pain control in severe cases 2
Common Pitfalls to Avoid
- Do not use topical acyclovir - it is substantially less effective than oral therapy 6
- Do not underdose or shorten treatment duration - this leads to treatment failure and increased complication risk 6
- Do not delay treatment beyond 72 hours when possible - efficacy decreases significantly 1, 2
- Do not fail to adjust doses in renal impairment - inappropriately high doses cause acute renal failure 1
- Do not expect extended acyclovir (21 days) or corticosteroids to prevent postherpetic neuralgia - neither strategy has proven effective for this outcome 7