antihistamine

noun

an·​ti·​his·​ta·​mine ˌan-tē-ˈhi-stə-ˌmēn 

-mən,

ˌan-tī-

: any of various compounds that counteract histamine in the body and that are used for treating allergic reactions (such as hay fever) and cold symptoms

antihistamine adjective

antihistaminic

ˌan-tē-ˌhi-stə-ˈmi-nik 

ˌan-tī-

adjective or noun

Examples of antihistamine in a Sentence

Recent Examples on the Web

Some people may need additional over-the-counter pain medication, antihistamines, or corticosteroids. —Meghan Overdeep, Southern Living, 11 July 2025

Take an oral nonprescription antihistamine (Benadryl) or one with loratadine (Alavert, Claritin, others). —Jalen Williams, Freep.com, 11 July 2025

Medications to take with caution in the heat include diuretics, ACE inhibitors, beta blockers, thyroid medication, antidepressants, antibiotics, antihistamines, NSAIDs, vitamin B6, and more. —Carrie Madormo, Verywell Health, 10 July 2025

Many common medications — including antihistamines, antidepressants and blood pressure drugs — can reduce saliva production, making the mouth more prone to tooth decay, infection and gum disease, WebMD states. —Reem Amro, FOXNews.com, 22 June 2025

Word History

First Known Use

1946, in the meaning defined above

Kids Definition

antihistamine

noun

an·​ti·​his·​ta·​mine ˌant-i-ˈhis-tə-ˌmēn 

-mən,

ˌan-ˌtī-

: any of various drugs used for treating allergic reactions and cold symptoms

Medical Definition

antihistamine

1 of 2 adjective

an·​ti·​his·​ta·​mine ˌant-i-ˈhis-tə-ˌmēn, ˌan-ˌtī-, -mən 

: tending to block or counteract the physiological action of histamine

human blood lacks antihistamine activity

antihistamine

2 of 2 noun

: any of various compounds that oppose the actions of histamine and are used especially for treating allergic reactions (as hay fever), cold symptoms, and motion sickness