Profile of H1-antihistamine prescriptions for chronic urticaria among Spanish allergists
E. Gonzalez Mancebo1; ML. Baeza2; JM. Beitia3; R. Cabañas4; PA. Galindo-Bonilla5; I. Losantos Garcia6; A. Moreno-Ancillo7; N. Prior8; M. Rodriguez-Rodriguez9; A. Rosado10; I. Sanchez-Matas11; T. Caballero12
1Hospital Universitario de Fuenlabrada, ARADyAL, Madrid, Spain; 2Hospital General Universitario Gregorio Marañón, CIBERER U761, IIS-GM, Madrid, Spain; 3Hospital Universitario de Guadalajara, ARADyAL, Guadalajara, Spain; 4University Hospital La Paz, IdiPAZ, CIBERER U754, PIELenRed, Madrid, Spain; 5Hospital General Universitario de Ciudad Real, Ciudad Real, Spain; 6La Paz University Hospital, Madrid, Madrid, Spain; 7Hospital General Nuestra Señora del Prado, Talavera de la Reina, Spain; 8Hospital Universitario Severo Ochoa, Madrid, Spain; 9Hospital Universitario Príncipe de Asturias, Departamento de Medicina y Especialidades Médicas, Alcala de Henares, Spain; 10Hospital Universitario Fundación Alcorcón, Alcorcón, Spain; 11Complejo Hospitalario Universitario de Toledo, Toledo, Spain; 12University Hospital La Paz, IdiPAZ, CIBERER U754, Madrid, Spain
Background

Urticaria is one of the most frequent causes of consultation in allergy departments. Second generation H1-antihistamines (2GH1AHs) at licensed doses are the first line therapy in chronic spontaneous urticaria (CSU). Aim: To analyse the prescribing habits of H1-antihistamines (H1AHs) for urticaria/angioedema treatment among Spanish allergists.

Method

An online survey was developed to analyse the prescribing habits of H1AHs for CSU, chronic-inducible-urticaria (CIU) and acquired-histaminergic-angioedema-without-wheals (AAE-IH). It was disseminated through the Spanish Society of Allergy and Clinical-Immunology among its members (April/May 2021), 128 responses were received. A descriptive statistical analysis was performed.

Results

Seventeen percent reported using first generation H1-antihistamines (1GH1AH) for CSU treatment, most of them due to prior experience. Besides, 97% used 2GH1AH, with bilastine (89%), cetirizine (87%) and ebastine (77%) being the most frequently used, followed by desloratadine (52%), levocetirizine (44%) and loratadine (41%). In patients with severe/refractory CSU, the most frequent attitude was to increase the H1AH dose (90%), with 87% referring not using mixed 2GH1AH/1GH1AH regimens. Regarding the maximum H1AH dose used, the quadruple dose of cetirizine, bilastine, loratadine, desloratadine and levocetirizine was used by the 69%, 67%, 49%, 47%, and 47% of prescribers, respectively. Besides, double doses and quadruple doses of ebastine-20mg were reached by 40% and 33%, respectively. Seventy-five percent believed that 4 times the licensed dose of 2GH1AH was safe enough. Those who thought it was not safe were concerned about drug interactions (72%), drowsiness (66%) and liver toxicity (56%). More than 80% used the same H1AHs for the treatment of CSU, CIU and AAE-IH.

Conclusion

2GH1AH were mostly used in the treatment of chronic urticaria by Spanish allergists, although a low percentage still used sedative 1GH1AH. The most frequently used H1AHs were bilastine, cetirizine and ebastine. In refractory cases of chronic urticaria, the most frequent attitude was to increase the dose of the same 2GH1AH and not to use mixed 2GH1AH/1GH1AH regimens. A high proportion believed that 4-times the authorized 2GH1AH dose was sufficiently safe, but the maximum dose achieved differed among H1AHs.