What are they?

What are antihistamines?

Antihistamines are medications used to treat allergies, and sometimes other symptoms or medical problems, such as motion sickness or insomnia.

There are several types of antihistamine. They work in different ways and have different effects. Please see our pages on cetirizine (Zyrtec), diphenhydramine (Benadryl) and loratadine (Alavert, Claritin) for information on a few types of antihistamine.

For information on other antihistamines, please call the poison center at 1-800-222-1222, chat online or text POISON to 85511.

Last Updated: Friday February 19th 2016