Allergists prefer second- vs. first-generation antihistamines, but some prefer both
Key takeaways:
- More than 75% of allergists preferred second-generation antihistamines for treating allergic rhinitis and urticaria.
- Out of five second-generation antihistamines, 60% ranked cetirizine as most effective.
SAN DIEGO — Across six different situations, more allergists preferred second- vs. first-generation antihistamines; however, in five situations, at least 18% reported preference for both antihistamines, according to a poster presented here.
This research was presented at the 2025 American Academy of Allergy, Asthma and Immunology/World Allergy Organization Joint Congress.
“We hope our findings will prompt allergists to consider their current clinical practice and more widely utilize second-generation antihistamines in most settings/patients,” Allison G. Hicks, MD, assistant professor of pediatric allergy and immunology at the University of Colorado School of Medicine and at Children’s Hospital Colorado, told Healio. “We also hope to highlight the lack of evidence for use of antihistamines for itch management in atopic dermatitis.”
Using survey data, Hicks and J. Andrew Bird, MD, evaluated responses from 85 practicing U.S. allergists and AAAAI members to understand when they use first-generation antihistamines vs. second-generation antihistamines in various situations.
Allergist characteristics
Within the total cohort, 25 allergists (29%) had more than 30 years in practice. Of the remaining allergists, 14 (16%) had 21 to 30 years in practice, 16 (19%) had 11 to 20 years, 13 (15%) had 5 to 10 years, 15 (18%) had less than 5 years and two (2%) did not answer.
According to the poster, allergists came from all four regions: Midwest (n = 23; 28%), South (n = 22; 27%), Northeast (n = 18; 22%) and West (n = 18; 22%).
The most common practice setting was academic practice (n = 28; 35%), followed by private group single specialty (n = 19; 23%), private solo practice (n = 14; 17%) and private group multispecialty (n = 12; 15%). Of the remaining eight allergists, one reported an active military practice setting, one reported a veterans’ hospital and six responded “other.”
Survey findings
When asked about the factors behind antihistamine selection, many allergists (91%) reported the safety profile of medication. Other frequently reported factors included efficacy (78%) and drug half-life (69%). Less than one-third of allergists reported price of drug (32%) or insurance coverage of drug (26%) as antihistamine selection factors, according to the poster.
Across six different situations, researchers found that allergists preferred second-generation antihistamines more than first-generation antihistamines; however, in most situations, around or more than 20% reported preference for both antihistamines.
For in-office challenges, most allergists preferred second- vs. first-generation antihistamines (67% vs. 11%), but 23% preferred both.
Similar to above, second-generation antihistamines were preferred over first-generation antihistamines in home allergy action plans (64% vs. 17%) and school allergy action plans (58% vs. 23%), but in each action plan, 18% of allergists had a preference for both.
Switching to treatment-specific situations, researchers reported that 96% of allergists preferred second-generation antihistamines for allergic rhinitis whereas the remaining 4% preferred both first- and second-generation.
In treating urticaria, the poster showed that 77% of allergists preferred second-generation antihistamines, 1% preferred first-generation and 21% preferred both.
When asked about treatment of AD, researchers found that the proportion of allergists who preferred second-generation antihistamines (45%) was close to the proportion who preferred both generations (39%). The remaining 16% preferred first-generation antihistamines.
“We found surprising the significant amount of practicing allergists who utilize older first-generation antihistamines, with known risks compared to newer antihistamines, in many clinical settings,” Hicks told Healio. “We also noted many providers utilize antihistamines in the treatment of itch in atopic dermatitis/eczema, although the data for its effectiveness are weak.”
In the second part of the survey, researchers asked allergists about perceived benefits of both antihistamines in patients with eczema. For the benefit of “addresses confounding atopic conditions,” a higher proportion of allergists reported second- vs. first-generation antihistamines (71% vs. 14%). This pattern was also true for “relieves pruritus,” as 55% reported second-generation antihistamines and 40% reported first-generation antihistamines.
In contrast, a greater proportion of allergists responded that “sedative effect” was a benefit of first- vs. second-generation antihistamines (75% vs. 3%), according to the poster.
Notably, 26% of allergists said first-generation antihistamines are “not beneficial for AD,” which was similar to the 23% of allergists who said this about second-generation antihistamines.
Researchers also asked allergists about prescribing comfort of both antihistamines by patient age group. A higher proportion of allergists reported being comfortable prescribing second-generation antihistamines vs. first-generation antihistamines to patients aged 6 months or younger (55% vs. 39%), patients aged 7 months to younger than 2 years (91% vs. 74%) and patients aged older than 55 years (94% vs. 48%).
In contrast, the proportion of allergists comfortable with prescribing second-generation antihistamines was similar to the proportion comfortable with prescribing first-generation antihistamines in patients aged 2 to 18 years (92% vs. 90%) and patients aged 19 to 55 years (96% vs. 91%), according to the poster.
Lastly, researchers asked allergists to rank five second-generation antihistamines — cetirizine, desloratadine, fexofenadine, levocetirizine and loratadine — by perceived efficacy, with one representing the most effective and five representing the least effective.
The second-generation antihistamine with the most allergists ranking it No. 1 was cetirizine with 45 allergists (60%). The poster further highlighted that levocetirizine had the second highest No. 1 ranking (n = 18; 24%), followed by fexofenadine (n = 14; 19%), desloratadine (n = 4; 5%) and loratadine with zero allergists.
The second-generation antihistamine with the most allergists ranking it No. 5 was loratadine with 32 allergists (44%). Desloratadine has the second highest No. 5 ranking (n = 26; 36%), according to researchers.
“We hope to next look at practice patterns in non-allergists, including primary care providers and emergency medicine providers,” Hicks told Healio. “We hope to spread awareness about the improved safety of second-generation antihistamines compared to first-generation antihistamines for most indications.”