An antihistamine is a drug used to counteract the effects of histamine, the chemical released by certain cells in the body during an allergic reaction. Although antihistamines do not change the cause of the allergic reaction, they do suppress the...

Antihistamines are medicines that relieve or prevent the symptoms of hay fever and other kinds of allergy. An allergy is a condition in which the body becomes unusually sensitive to some substance, such as pollen, mold spores, dust particles, certain...

Antihistamines are drugs used to relieve the symptoms of allergies caused by histamine, an amino acid derivative found throughout the body. Histamine was first recognized and suggested as the cause of allergic reactions by Henry Dale (1875-1968) and...

Antihistamines are drugs used to relieve the symptoms of allergies caused by histamine, an amino acid derivative found throughout the body. Histamine was first recognized and suggested as the cause of allergic reactions by Henry Dale (1875-1968) and...

Synthetic drug that counteracts the effects of released histamine in the body. Antihistamines compete with histamine at one of the three types of histamine receptors, preventing allergic attacks (&see; allergy) or inflammation. Some antihistamines also...

A drug used to counter the effects of HISTAMINE; typically given to combat allergic reactions, antihistamines have a SEDATIVE effect that is mediated through an action On the CENTRAL NERVOUS...

A drug that acts to counter the effects of HISTAMINE. It is used especially in the treatment of allergic...

An H1-antihistamine is a histamine antagonist that serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions, through action at the H1 receptor. Only agents where the main therapeutic...