antihistamine. Antihistaminic Pharmacology An agent that counteracts the effects of histamine released during allergic reactions by blocking histamineâH 1 receptors Adverse effects Dry mouth, drowsiness, urine retention in â, tachycardia.hile the term antihistamine can broadly include any agent that blocks any histamine receptor, in practice it is usually used to denote those blocking the H 1 type of receptors (H1 receptor antagonists), those involved in allergic reactions.
While all of these Military service branches are uniformed, have. weapons, ranks and other such details that are. similar, the specific missions and focus of. each service is quite different. The US Army is charged as the primary land. combat force.
Marine Division. There are three Marine divisions in the active force and one in the Reserve. A division is the largest Marine ground combat organization of a MEF. Divisions are designated with Arabic numerals. Illustrations of division unit designations are provided below: 1  Division - 1st Marine Division (1st MarDiv).