Hypotension

Hypotension
Classification and external resources
Specialty	Critical care medicine
ICD-10	I95
ICD-9-CM	458 or more commonly used 796.3
DiseasesDB	6539
MedlinePlus	007278
Patient UK	Hypotension
MeSH	D007022
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Hypotension is low blood pressure, especially in the arteries of the systemic circulation.Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. A systolic blood pressure of less than 90 millimeters of mercury (mm Hg) or diastolic of less than 60 mm Hg is generally considered to be hypotension. However, in practice, blood pressure is considered too low only if noticeable symptoms are present.

Hypotension is the opposite of hypertension, which is high blood pressure. It is best understood as a physiological state, rather than a disease. Severely low blood pressure can deprive the brain and other vital organs of oxygen and nutrients, leading to a life-threatening condition called shock. Though often associated with shock, hypotension is not necessarily indicative of it.

For some people who exercise and are in top physical condition, low blood pressure is a sign of good health and fitness. For many people, excessively low blood pressure can cause dizziness and fainting or indicate serious heart, endocrine or neurological disorders.

The cardinal symptoms of hypotension include lightheadedness or dizziness.

If the blood pressure is sufficiently low, fainting and often seizures occur.

Low blood pressure is sometimes associated with certain symptoms, many of which are related to causes rather than effects of hypotension:

Low blood pressure can be caused by low blood volume, hormonal changes, widening of blood vessels, medicine side effects, anemia, heart problems or endocrine problems.

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