Antihistamines, 1st Generation, Antiemetic Agents
Diphenhydramine is an
used for treating
Histamine is released by the body during several types of allergic reactions
and--to a lesser extent--during some viral infections, such as the
. When histamine binds to receptors on cells, it stimulates changes
within the cells that lead to the release of chemicals that
compete with histamine for cell
receptors and bind to the receptors without stimulating the cells. In addition,
they prevent histamine from binding and stimulating the cells.
Diphenhydramine also blocks the action of acetylcholine (anticholinergic
effect) and is used as a sedative because it causes drowsiness.