What is the preferred choice between lidocaine (local anesthetic) patch and lidocaine cream for localized pain relief in patients, particularly those with post-herpetic neuralgia or neuropathic pain?

Lidocaine Patch vs Lidocaine Cream for Localized Pain Relief

For localized neuropathic pain, particularly postherpetic neuralgia, the lidocaine patch is strongly preferred over lidocaine cream due to superior sustained drug delivery, stronger guideline support, and better clinical outcomes.

Primary Recommendation

The lidocaine patch (5% prescription or 4% OTC) should be the first-line topical lidocaine formulation for neuropathic pain conditions, especially postherpetic neuralgia, with cream reserved only for areas where patches cannot adhere properly. 1, 2, 3

Key Evidence Supporting Patch Superiority

• The American Academy of Neurology recommends lidocaine patches as first-line therapy for postherpetic neuralgia with a number needed to treat (NNT) of 2, making it one of the most effective treatments available for this condition. 3

• The patch provides sustained drug delivery over 12-24 hours with gradual medication release, whereas cream provides only immediate but shorter-duration relief. 2

• Approximately 60% of patients with postherpetic neuralgia achieve moderate to complete pain relief with proper 12-hour daily patch application. 3, 4

• The American Academy of Neurology guideline (though retired in 2018) classified the lidoderm patch as "possibly effective" for painful diabetic neuropathy based on Class III evidence showing 20-30% reduction in pain scores and 70% of patients experiencing more than 30% decrease in pain. 1

Application Protocol for Patches

• Apply up to 3-4 patches simultaneously to intact skin covering the painful area. 2, 3, 5

• Standard regimen: 12 hours on, 12 hours off (do not exceed 12 hours of continuous application to minimize skin irritation and ensure adequate patch-free period). 3, 5

• Available formulations: 4% over-the-counter concentration or 5% prescription strength. 2, 3

• The newer 1.8% topical system offers bioequivalent delivery to 5% patches but with 19-fold decrease in drug load (36 mg versus 700 mg) and superior adhesion. 6

When to Consider Cream

Lidocaine cream should only be used as a complementary agent to patches, not as primary therapy:

• Apply cream to areas where patches cannot adhere well due to body contours or hair. 2

• Use cream to provide immediate relief while waiting for patch effect to establish. 2

• For pre-treatment before capsaicin application: apply 4% lidocaine for 60 minutes and wipe off before applying capsaicin 8% patch. 1

Safety Profile and Monitoring

• Systemic lidocaine levels remain within safe range even with four patches applied over 24 hours, with highest measured blood levels at only 0.1 micrograms/ml. 3, 5, 7

• Adverse reactions are rare, mild, and mostly limited to local skin reactions (rash or irritation). 5, 7, 8

• Monitor for signs of systemic absorption: dizziness, confusion, bradycardia, drowsiness, disorientation, muscle twitching. 3, 5

• Perform periodic skin checks for irritation or sensitization. 2

Critical Contraindications and Precautions

Absolute contraindications:

• Advanced liver failure (hepatic impairment reduces lidocaine clearance by 60%). 2
• Application to broken or inflamed skin (dramatically increases systemic absorption and toxicity risk). 2, 3, 5
• Known hypersensitivity to amide anesthetics. 2, 5

Important precautions:

• Avoid excessive heat application over patches, as this increases systemic absorption. 2, 3, 5
• Remove patches before starting intravenous lidocaine therapy. 2, 3, 5
• Avoid using within 4 hours of other local anesthetic interventions to prevent cumulative toxicity. 2, 3

Combination Therapy Algorithm When Patches Alone Are Insufficient

If inadequate pain relief after 4 weeks of patch therapy:

1. Add gabapentin starting at 50-100 mg three times daily, titrating to 900-3600 mg daily for neuropathic pain components. 1, 3

2. Consider pregabalin 50 mg three times daily, titrated to 100 mg three times daily if gabapentin fails. 1, 3

3. Add capsaicin 8% patch for single application providing pain relief lasting up to 90 days (pre-treat with lidocaine cream for 60 minutes before capsaicin application). 1, 3

4. Consider tricyclic antidepressants or SNRIs if inadequate response to gabapentinoids. 1, 3

5. Add non-pharmacological therapies such as physical therapy, yoga, or cognitive behavioral therapy. 1, 2

Clinical Context and Limitations

• Lidocaine patches are most appropriate for well-localized pain and unlikely to benefit central neuropathic pain or widespread pain distribution. 2, 3

• The patch is equally effective in longstanding postherpetic neuralgia (mean 28 months from herpes zoster onset), though earlier initiation is prudent. 4

• Approximately 43% of patients who do not respond by Day 7 experience improvement in pain intensity by Day 14, so allow adequate trial duration of at least 4 weeks before switching treatments. 2, 4