What is the recommended pain management for shingles?

Pain Management for Shingles

Gabapentin is recommended as the first-line oral pharmacological treatment for shingles-related neuropathic pain, with typical adult dosing titrating up to 2400 mg per day in divided doses. 1

Initial Pain Management Approach

• For acute shingles pain, begin with topical analgesics such as lidocaine, oral acetaminophen, and oral nonsteroidal anti-inflammatory drugs (NSAIDs) 1
• Antiviral therapy should be initiated as soon as possible, ideally within 72 hours of rash onset, using one of the following:
  • Famciclovir 500 mg every 8 hours for 7 days 2
  • Acyclovir or valacyclovir are alternative options 3

Stepwise Pain Management Algorithm

Step 1: First-line Treatments

• Gabapentin is the first-line oral medication for neuropathic pain associated with shingles 1
  • Start with low doses and titrate up to 2400 mg daily in divided doses
  • This medication also improves sleep scores, though somnolence occurs in about 80% of patients 1
• Topical capsaicin is strongly recommended for management of peripheral neuropathic pain 1
  • An 8% dermal patch or cream can be applied to the affected area 1

Step 2: If Inadequate Response to Gabapentin

• Consider a trial of serotonin-norepinephrine reuptake inhibitors (SNRIs) 1
• Consider tricyclic antidepressants (TCAs) 1
  • Secondary amine TCAs (nortriptyline, desipramine) are preferred due to fewer anticholinergic side effects 1
  • Start with low doses at bedtime and titrate slowly
  • Use with caution in patients with cardiac disease; obtain ECG for patients over 40 years 1
• Consider pregabalin specifically for post-herpetic neuralgia 1

Step 3: For Severe or Refractory Pain

• For severe breakthrough pain in patients at low risk for opioid misuse, consider short-acting opioid analgesics in limited amounts 1
• Tramadol may be considered as an alternative to conventional opioids, particularly in patients with cardiopulmonary compromise 1
• For patients with severe pain not responding to first-line agents, conventional opioids like codeine, hydrocodone, or morphine may be necessary 1

Special Considerations

• Pain management should be initiated during the diagnostic evaluation and continued throughout treatment 1
• The risk of developing post-herpetic neuralgia (PHN) increases with age and is defined as pain persisting for at least 90 days after acute herpes zoster 4
• For post-herpetic neuralgia specifically, evidence supports:
  • Tricyclic antidepressants (NNT = 2.64) 1
  • Certain opioids including oxycodone, extended-release morphine, and methadone (NNT = 2.67) 1
  • Gabapentin (NNT = 4.39) 1
  • Pregabalin (NNT = 4.93) 1
  • Topical lidocaine patches (NNT = 2) 1

Monitoring and Follow-up

• Reassess pain frequently and adjust treatment based on response 1
• If substantial pain relief is achieved (pain reduced to ≤3/10) with tolerable side effects, continue the current treatment 1
• If only partial pain relief is achieved (pain remains ≥4/10), add another first-line medication 1
• If inadequate pain relief occurs (<30% reduction) after an adequate trial, switch to an alternative first-line medication 1
• For patients whose pain is controlled, any new report of pain should be carefully investigated and may require treatment adjustments 1

Cautions and Pitfalls

• Opioid analgesics should not be prescribed as first-line agents for long-term management of neuropathic pain 1
• Cardiac toxicity is a concern with tricyclic antidepressants; use with caution in patients with cardiac disease 1
• Adequate trials of medication may take 6-8 weeks, including 2 weeks at the highest tolerated dose 1
• Anticonvulsants (pregabalin and gabapentin) should be used with caution due to potential side effects 1