There are also syndromes that can cause hypotension in patients including orthostatic hypotension, vasovagal syncope, and other rarer conditions.For many people, excessively low blood pressure can cause dizziness and fainting or indicate serious heart, endocrine or neurological disorders.For some people who exercise and are in top physical condition, low blood pressure could be normal. A single session of exercise can induce hypotension and water-based exercise can induce a hypotensive response.Treatment of hypotension may include the use of intravenous fluids or vasopressors. When using vasopressors, trying to achieve a mean arterial pressure (MAP) of greater than 70 mmHg does not appear to result in better outcomes than trying to achieve a MAP of greater than 65 mmHg in adults. Signs and symptoms
The primary symptoms of hypotension are lightheadedness or dizziness.If the blood pressure is sufficiently low, fainting (syncope) may occur.Low blood pressure is sometimes associated with certain symptoms, many of which are related to causes rather than effects of hypotension:

Causes
Low blood pressure can be caused by low blood volume, hormonal changes, widening of blood vessels, medicine side effects, severe dehydration, anemia, vitamin B12 deficiency, anaphylaxis, heart problems or endocrine problems.Reduced blood volume, hypovolemia, is the most common cause of hypotension. This can result from hemorrhage; insufficient fluid intake, as in starvation; or excessive fluid losses from diarrhea or vomiting. Hypovolemia can be induced by excessive use of diuretics.
When a great deal of blood is diverted to the intestines (a kind of "splanchnic blood pooling") to facilitate digestion and absorption, the body must increase cardiac output and peripheral vasoconstriction to maintain enough blood pressure to perfuse vital organs, such as the brain. Postprandial hypotension is believed to be caused by the autonomic nervous system not compensating appropriately, because of aging or a specific disorder.Hypotension is a feature of Flammer syndrome, which is characterized by cold hands and feet and predisposes to normal tension glaucoma.Hypotension can be a symptom of relative energy deficiency in sport, sometimes known as the female athlete triad, although it can also affect men. Pathophysiology
Blood pressure is continuously regulated by the autonomic nervous system, using an elaborate network of receptors, nerves, and hormones to balance the effects of the sympathetic nervous system, which tends to raise blood pressure, and the parasympathetic nervous system, which lowers it. The vast and rapid compensation abilities of the autonomic nervous system allow normal individuals to maintain an acceptable blood pressure over a wide range of activities and in many disease states. Even small alterations in these networks can lead to hypotension. Diagnosis
For most adults, the optimal blood pressure is below 120/80 mmHg. If the systolic blood pressure is <90 mmHg or the diastolic blood pressure is <60 mmHg, it would be classified as hypotension.