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

Do not use antihistamines for severe food allergies that require using an EpiPen, as this can delay necessary treatment and be life-threatening. —Wendy Wisner, Health, 18 Apr. 2025

This would be a new cost to health plans because patients often bear their own over-the-counter antihistamine med costs. —Dylan Scott, Vox, 15 Apr. 2025

Which Meds Aren’t Safe To Use Daily? Generally, antihistamines, as well as antihistamines combined with decongestants, aren’t recommended for long-term use. —Jillian Kubala, Health, 28 Apr. 2025

Of course, there are the usual treatments—antihistamines, nasal sprays, decongestants, etc.—but what about a shot to relieve your symptoms? —Thomas G. Moukawsher, MSNBC Newsweek, 24 Apr. 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