hypotension

hypotension Blood pressure that is below the normal expected for an individual in a given environment. Blood pressure normally varies greatly with activity, age, medications, and underlying medical conditions. Hypotension can result from conditions of the nervous system, conditions that do not begin in the nervous system, and drugs. Neurological conditions that can lead to low blood pressure include changing position from lying to a more vertical position (postural hypotension), stroke, shock, Parkinson’s disease, neuropathy, and fright. Nonneurological conditions that can cause low blood pressure include bleeding, sepsis, dehydration, heart disease, adrenal insufficiency, pregnancy, prolonged bed rest, poisoning, and blood transfusion reactions. Severe hypotension is referred to as shock or hypovolemic shock. Treatment of mild hypotension may not be necessary, although the severe lowering of blood pressure known as shock is life-threatening and requires immediate medical treatment. Hypotension is the opposite of hypertension (abnormally high blood pressure). See also hypotension, orthostatic.