antihistamine

American  

[an-ti-his-tuh-meen, -min] / ˌæn tɪˈhɪs təˌmin, -mɪn /

noun

Physiology, Pharmacology.

• antihistamines
  plural

1. any of certain compounds or medicines that neutralize or inhibit the effect of histamine in the body, used chiefly in the treatment of allergic disorders and colds.

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antihistamine British  

/ -mɪn, ˌæntɪˈhɪstəˌmiːn /

noun

1. any drug that neutralizes the effects of histamine, used esp in the treatment of allergies

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antihistamine Scientific  

/ ăn′tē-hĭs′tə-mēn′ /

1. Any of various drugs that relieve cold or allergy symptoms by blocking the action of histamine.

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Other Word Forms

Noun Inflected Forms

• antihistamines
  plural

Etymology

Origin of antihistamine

First recorded in 1930–35; anti- + histamine

Explanation

An antihistamine is a type of drug you might take if you suffer from allergies. If your friend's cat makes your throat itch and your eyes swell, you should probably take an antihistamine. Antihistamines work by suppressing the effects of histamine in your body — this is substance released by your cells when you're exposed to allergens, or things you're allergic to. It's histamine that makes you sneeze or get itchy hives, and it's antihistamine that soothes this reaction. This scientific word comes from anti-, "against," histidine, an amino acid, and amine, a certain kind of organic compound.

Example Sentences

See Examples For:

antihistamine antihistamines

These sublethal effects can be compared to the way an over-the-counter antihistamine may relieve allergy symptoms while also causing drowsiness.

From Science Daily ● Aug. 6, 2026

And patients may also be given medications after an episode including a type of antihistamine, but they have sedative effects that can cause more problems, such as falls.

From The Wall Street Journal ● Apr. 15, 2026

Wright gives the example of a "hyper-niche" program about pollen counts in a specific city, heard by a few dozen people that can attract antihistamine advertisers.

From Barron's ● Oct. 13, 2025

If you’re highly allergic to mosquitoes, the American Mosquito Control Assn. said you may need a cream with Benadryl or a similar antihistamine.

From Los Angeles Times ● Jul. 29, 2024

Mom gave me some antihistamine pills after I got out of the bath.

From "100 Sideways Miles" by Andrew Smith

"It's been difficult. I've had to take a lot of antihistamines, which have made me quite drowsy. I've been waking up in the night itching," she said.

From BBC ● Aug. 8, 2026

At this point, my antihistamines have started to wear off.

From The Wall Street Journal ● Apr. 6, 2026

The first-aid kit in your “go-bag” should have standard supplies, but double-check that you’ve got bandages and gauze, medical tape, antibiotic cream, antacids, anti-diarrhea medications, antihistamines and over-the-counter pain relievers.

From Los Angeles Times ● Jan. 8, 2025

Current therapies used to help manage symptoms include over-the-counter and prescription itch relief ointments and anti-inflammatory drugs such as antihistamines and corticosteroids.

From Science Daily ● Jun. 6, 2024

I was lathered up in calamine lotion and had swallowed a bucketful of antihistamines with my morning orange juice.

From "City of the Plague God" by Sarwat Chadda