Antihistamines inhibit in the body, the effect of the Gewebshormons histamine. You can alleviate this typical Heuschupfen-symptoms such as a runny nose or itchy eyes, caused by excessive Histamine release. Among the most commonly used to treat hay fever used antihistamines the active ingredients, loratadine and cetirizine. They both belong to the H1-antihistamines of the second Generation. In contrast to older antihistamines you have almost no side effects. Especially the sedative effect, which has previously led to a strong fatigue in the patients, is much less pronounced. Inform yourself thoroughly about the effects and side effects of antihistamines.