Why is the Lidoderm (lidocaine) patch applied for only 12 hours?

Why Lidoderm Patch is Applied for Only 12 Hours

The standard duration for lidocaine patch application is 12 hours, followed by a 12-hour removal period, to provide effective pain relief, allow skin recovery, and minimize the risk of cumulative lidocaine absorption and skin irritation. 1

Rationale for 12-Hour Application

The 12-hour application/12-hour removal cycle serves several important purposes:

1. Skin Recovery and Safety

   • Allows the skin underneath the patch to recover, preventing irritation and sensitization
   • Minimizes the risk of cumulative lidocaine absorption that could lead to systemic effects
   • Maintains the excellent safety profile of lidocaine patches, which have a risk of adverse events similar to placebo 1

2. Efficacy Considerations

   • Clinical trials have demonstrated that the 12-hour application period provides effective pain relief for conditions like postherpetic neuralgia 2
   • The analgesic effect persists even during the 12-hour "off" period due to lidocaine's mechanism of action

3. Pharmacological Principles

   • Lidocaine provides analgesic relief by blocking neuronal sodium channels 3
   • The drug penetrates into the skin to produce an analgesic effect without causing a complete sensory block 4
   • The 12-hour cycle maintains therapeutic levels while preventing toxicity

Clinical Evidence Supporting This Approach

The 12-hour application protocol has been validated in multiple clinical trials:

• Studies have shown that applying lidocaine patches for 12 hours daily provides significant reductions in pain intensity and improvements in quality of life 2
• Long-term studies using the 12-hour application protocol have demonstrated continued efficacy and safety 5
• The FDA approval for lidocaine patches is based on this application schedule, both for the original 5% formulation and the newer 1.8% system 4

Important Considerations for Clinical Practice

• Proper Application: Apply patches directly to the most painful area for maximum effectiveness 1
• Adequate Trial Period: Allow at least 4 weeks of consistent use before determining efficacy 1
• Monitoring: Watch for local skin reactions such as redness or irritation at the application site 1
• Patient Education: Instruct patients on the importance of adhering to the 12-hour on/12-hour off schedule

Advantages of Lidocaine Patches in Pain Management

• Topical lidocaine patches avoid risks associated with NSAIDs and provide effective pain relief with fewer side effects compared to opioid-based treatments 1
• They are particularly suitable for older adults with chronic pain due to minimal systemic effects 1
• Lidocaine patches can be used as part of multimodal pain management alongside other analgesics 1

By following the recommended 12-hour application protocol, clinicians can maximize the benefits of lidocaine patches while minimizing potential risks, providing effective pain relief for patients with conditions like postherpetic neuralgia and other neuropathic pain syndromes.