Note Proper Use of Antihistamines During Spring Allergy Season

Although antihistamines are commonly used to manage hives, sneezing, and watery eyes during allergy season, many patients may be taking their medications incorrectly, according to Derek Chu, MD, PhD, a McMaster University allergy expert and clinical scholar.

“People need to rethink what they stock in their home cabinets as allergy medicines, what hospitals keep on formulary, and what policymakers recommend,” Chu said in a press release. “The message needs to get out. This publication is on time for the spring allergy season and as COVID vaccines roll out, for which rashes are common and antihistamines can be helpful.”

Co-author Gordon Sussman, MD, FRCP, FACP, DIP.ABIM, FAAAAI, said in the press release that there are new second generation antihistamines that prescribers should know about. Their new study, published in the Canadian Medical Association Journal, lists 5 things to know about proper antihistamine use.

Antihistamines are among the most commonly and incorrectly used medications worldwide, according to the press release. Their best use is for the management of hay fever and outbreaks of hives, and not for management of asthma, eczema, coughs, or insomnia.

Notably, first-generation antihistamines are associated with substantial and sometimes fatal adverse effects (AEs). These antihistamines are ones with diphenhydramine, chlorpheniramine, or hydroxyzine, which can cause drowsiness and affect cognitive functions, such as school performance. Overdosing with these types of antihistamines can cause death and are potentially dangerous for both young and older people.

Second-generation antihistamines are safer and just as affordable and as effective as first-generation antihistamines, according to the study authors. Later-generation antihistamines are proven to be more effective and last longer with less severe AEs, such as drowsiness, according to the study authors.

In their fourth point, the authors said antihistamines should not be used instead of epinephrine to treat anaphylaxis. Oral drugs can be used in combination with epinephrine injections to treat anaphylactic reactions, but they are not a proper substitute.

Finally, they said most antihistamines are safe to use during pregnancy and breastfeeding. Researchers have shown that antihistamines at standard doses do not harm fetuses during pregnancy and may be used during breastfeeding. Similarly, the researchers said they are safe for children to use.

“These are new modern second-generation antihistamines that are potent, specific, fast acting, and of proven safety which everyone should be using to treat allergic rhinitis and hives,” Sussman said in the press release.

REFERENCE

Are you using antihistamines properly? [news release]. EurekAlert; April 6, 2021. https://www.eurekalert.org/pub_releases/2021-04/mu-ayu040121.php. Accessed April 8, 2021.