[Long-term effectiveness of topical analgesics]

Area of Science:

• Neurology
• Pain Management
• Dermatology

Background:

• Neuropathic pain presents a significant challenge in treatment.
• Topical analgesics offer a low-systemic side effect profile.
• Long-term effectiveness data for topical analgesics are limited.

Purpose of the Study:

• To evaluate the long-term effectiveness of topical capsaicin (C), lidocaine (L), and botulinum toxin type A (B) for neuropathic pain.
• To assess patient-reported pain reduction and changes in analgesic prescription.
• To identify reasons for discontinuation of topical analgesic therapy.

Main Methods:

• A retrospective analysis of 265 patients treated with C, L, and/or B between 2008-2017.
• Telephone interviews with 205 patients to gather feedback on pain reduction and medication use.
• Data collection on pain history, intensity (NRS), and treatment outcomes.

Main Results:

• Lidocaine (L) demonstrated the highest primary (57%) and long-term (60%) responder rates.
• Botulinum toxin type A (B) showed primary (52%) and long-term (37%) response rates.
• Capsaicin (C) had lower responder rates (23% primary, 15% long-term).
• Long-term responders using B most frequently reduced analgesic use (74%).

Conclusions:

• Topical lidocaine (L) and botulinum toxin type A (B) are effective off-label treatments for neuropathic pain.
• These agents demonstrate high primary response rates, unlike capsaicin (C).
• Long-term treatment with L and B provides sustained benefits, with B aiding in reduced analgesic consumption.