Is lidocaine (local anesthetic) and prilocaine (local anesthetic) effective for pain relief in shingles?

Lidocaine-Prilocaine for Shingles Pain Management

Topical lidocaine and prilocaine can effectively relieve pain associated with shingles (herpes zoster) and should be considered as part of a multimodal pain management approach for patients with this condition. 1, 2

Mechanism and Efficacy

• Lidocaine blocks sodium ion channels required for the initiation and conduction of neuronal impulses, resulting in local anesthesia after topical application, which helps reduce the neuropathic pain associated with shingles 3
• Lidocaine patch 5% has demonstrated significant pain relief during both rest and movement in patients with acute herpes zoster compared to placebo, with mean pain reduction differences of 14.7% during rest and 10.4% during movement 2
• Topical lidocaine gel has been shown to effectively relieve postherpetic neuralgia pain through direct drug action on painful skin, with significant pain relief reported at multiple time points 4
• The combination of lidocaine and prilocaine in a eutectic mixture (EMLA) provides dermal analgesia following topical application and has demonstrated efficacy in various painful dermatological conditions 5

Application Guidelines

• For acute herpes zoster, lidocaine patches should be applied to intact skin (avoiding areas with active blisters) at 12-hour intervals twice daily 2
• Lidocaine patches are available in over-the-counter 4% concentration or prescription 5% strength and can be applied for 12-24 hours per day 3
• For cranial herpes zoster, topical lidocaine gel can be applied without occlusion for up to 8 hours; for limb or torso involvement, application under occlusion for 24 hours may be more effective 4
• When using lidocaine-prilocaine cream, apply to intact skin only and allow sufficient time for effectiveness as per package insert 1

Integration with Other Therapies

• Topical lidocaine should be used as part of a comprehensive pain management strategy for shingles that may include:
  • Systemic analgesics including antidepressants, anticonvulsants, and opioids when necessary 1
  • Integrative interventions such as psychological and physical approaches 1
  • Corticosteroids for radiculopathies associated with nerve compression 1

Safety Considerations

• Lidocaine patch 5% has demonstrated a favorable safety profile with low incidence of adverse events in acute herpes zoster patients 2
• Avoid application to broken or inflamed skin, and monitor for signs of systemic absorption such as dizziness or confusion 3
• Blood lidocaine concentrations typically remain within safe ranges when used as directed, though monitoring may be necessary with extensive use 6
• The combination of lidocaine and prilocaine has a favorable tolerability profile, with transient and mild skin blanching and erythema being the most frequent adverse events 5

Special Considerations

• For procedure-related pain associated with shingles treatment, lidocaine and prilocaine can be used with sufficient time for effectiveness 1
• Physical approaches such as cutaneous warming, vibration, or use of warm solution may enhance the effectiveness of topical anesthetics 1
• Buffering of lidocaine (not recommended for bupivacaine) can decrease injection pain if infiltrative anesthesia is needed 1
• For postherpetic neuralgia (PHN), topical lidocaine has shown efficacy when applied directly to painful skin areas, but not when applied to remote sites 4

Limitations and Monitoring

• While topical lidocaine is effective for many patients with shingles pain, some may require additional or alternative therapies 6
• Regular assessment of pain relief and monitoring for adverse skin reactions is recommended 3
• For patients with inadequate pain relief from topical agents alone, consider adding systemic medications such as anticonvulsants or antidepressants 1
• The National Comprehensive Cancer Network guidelines support the use of topical local anesthetics for neuropathic pain, including pain similar to that experienced in shingles 1