Effectiveness of Botulinum Toxin Type A for Trichodynia Associated with Hair Loss Disorders: A Retrospective Study

INTRODUCTION: Trichodynia significantly impairs quality of life in patients with hair loss, for which effective treatments remain limited. This study evaluates the use of intradermal botulinum toxin type A (BTA) in patients with trichodynia unresponsive to conventional therapies. METHODS: We retrospectively analyzed 21 patients with trichodynia and with alopecia who had discontinued or refused systemic treatments. BTA was administered using the Nappage technique. Symptom severity and disease activity were assessed using the Visual Analogue Scale (VAS) and the Lichen Planopilaris Activity Index (LPPAI), respectively. RESULTS: Most patients (90.5%) reported symptomatic improvement within 18.3 days on average. Mean VAS scores declined from 8.0 to 2.0 at 3 months and reached 0.0 by 6 months. In cicatricial alopecia, LPPAI scores showed significant reduction. Treatment was well tolerated, with only minor adverse effects. DISCUSSION: The clinical improvement observed may be explained by the neuromodulatory effects of BTA on neurogenic inflammation, including inhibition of substance P and CGRP release. Notably, patients with inflammatory scarring alopecias showed a more pronounced response than those with noncicatricial alopecias, suggesting that BTA may be particularly beneficial in conditions where pain is linked to active perifollicular inflammation. CONCLUSIONS: Intradermal BTA appears to be a safe and potentially effective treatment for trichodynia, particularly in patients with scarring alopecia who are not candidates for systemic therapy. These findings warrant further validation in controlled studies.