Evaluation of antihistamine efficacy in combined therapy for alopecia areata

BACKGROUND: In treating alopecia areata, antihistamines such as fexofenadine and ebastine are considered adjuvant therapy, primarily in patients with concomitant allergic diseases. The insufficient understanding of their mechanisms of action and limited evidence of their efficacy in alopecia areata highlight the need for further research.

AIM: To evaluate the efficacy of ebastine and fexofenadine combined with local therapy for the treatment of alopecia areata.

MATERIALS AND METHODS: A 12-week prospective comparative cohort study included 91 patients with alopecia areata aged ≥12 years, some with atopic conditions. Participants were randomized into two groups: the main group (n = 43) received standard therapy for alopecia areata (intradermal injection of betamethasone suspension, 0.2 mL/cm², not exceeding 1 ml, once) combined with oral ebastine 20 mg or fexofenadine 120 mg daily for 28 days; the comparison group received betamethasone alone. Antihistamines in the main group were prescribed for allergy management. Both groups were assessed for clinical and anamnestic data, baseline and post-treatment alopecia severity via SALT scores (%), and hair regrowth rates.

RESULTS: The groups were matched in age, gender and current episode duration characterized by the active stage of alopecia areata. Baseline SALT indicated mild severity (median 22.4 %, interquartile range 13.45 in the main group; and median 19.3 %, interquartile range 15.53 % in the comparison group; p >0.05). All patients in the main group and 60.4 % of the comparison group had atopic comorbidities. At 12 weeks, the main group showed a reduction in SALT scores to a median value of 5.4 % (interquartile range 9.35 %), significantly lower than the comparison group (12.65 %, interquartile range 18.65 %; p = 0.002). Hair regrowth (%) was higher in the main group (72.04 %, interquartile range 35.73 % vs. 40.97 %, interquartile range 93.32 %; p = 0.01). Increased hair loss or negative regrowth occurred in 4.65 % of the main group vs. 31.25 % of the comparison group.

CONCLUSION: The combination of fexofenadine or ebastine with local therapy significantly reduces alopecia areata severity and promotes hair regrowth compared to only topical treatment. These findings suggest a potential role of antihistamines in stabilizing the pathological process in hair follicles, enhancing treatment efficacy. Further investigation into histamine receptors’ role in alopecia areata pathogenesis is warranted.