Antihistamines as adjunct therapy effective in alopecia areata treatment

Antihistamines proved to be efficacious as adjunct therapy in the treatment of alopecia areata, whereas antihistamines as monotherapy and dupilumab warrant further research, according to a study.

“Approximately 30% to 40% of alopecia areata (AA) patients have atopic dermatitis,” Christine T. Pham, MD, professor of medicine in the division of rheumatology at Washington University in St. Louis, and colleagues wrote. “Studies suggest that antihistamines and dupilumab may be effective treatments; however, the potential benefit of these therapies as either adjunct or monotherapy has yet to be elucidated.”

Pham and colleagues used PubMed, Cochrane and CINAHL databases to conduct a literature search for articles describing the use of antihistamines or dupilumab for AA, according to PRISMA guidelines, in August 2021. Articles discussing AA development as an adverse event to these therapies were also included.

The study included 42 articles involving 395 patients with AA. The most common regimens for antihistamines were twice-daily oxatomide 30 mg, once-daily fexofenadine 60 mg or 120 mg and once-daily ebastine 10 mg.

The majority of patients who were administered antihistamines reported increased hair growth, decreased pruritus and decreased erythema. In AA treatment, dupilumab also showed significant hair growth in 23 patients and no change in three patients; however, in atopic dermatitis treatment, dupilumab was implicated as the cause of AA in 21 patients, drug-induced alopecia in two patients and AA-like psoriasis in one patient.

“The efficacy of dupilumab in the treatment of AA and its association with drug-induced AA warrants further studies,” Pham and colleagues wrote. “Current clinical trials will hopefully elucidate this association.”