My WebMD Sign In, Sign Up

Ask Your Question

WebMD Answers

120 Characters remaining
120 Characters remaining
  • First, try and keep your question as short as possible.
  • Include specific words that will help us identify questions that may already have your answer.
  • If you don't find your answer, you can post your question to WebMD Experts and Contributors.

Close

Posted: | Report This Report Question |
 

Answers From Experts & Organizations (1)

8,020 Answers
294,533 Helpful Votes
343 Followers
A.

Hypotension is the medical term for low blood pressure (less than 90/60).

A blood pressure reading appears as two numbers. The first and higher of the two is a measure of systolic pressure, or the pressure in the arteries when the heart beats and fills them with blood. The second number measures diastolic pressure, or the pressure in the arteries when the heart rests between beats.

Optimal blood pressure is less than 120/80 (systolic/diastolic). In healthy people, low blood pressure without any symptoms is not usually a concern and does not need to be treated. But low blood pressure can be a sign of an underlying problem -- especially in the elderly -- where it may cause inadequate blood flow to the heart, brain, and other vital organs.

Chronic low blood pressure with no symptoms is almost never serious. But health problems can occur when blood pressure drops suddenly and the brain is deprived of an adequate blood supply. This can lead to dizziness or lightheadedness. Sudden drops in blood pressure most commonly occur in someone who's rising from a prone or sitting position to standing. This kind of low blood pressure is known as postural hypotension or  orthostatic hypotension. Another type of low blood pressure can occur when someone stands for a long period of time, This is called neurally mediated hypotension.

Postural hypotension is considered a failure of the cardiovascular system or nervous system to react appropriately to sudden changes. Normally, when you stand up, some blood pools in your lower extremities. Uncorrected, this would cause your blood pressure to fall. But your body normally compensates by sending messages to your heart to beat faster and to your blood vessels to constrict. This offsets the drop in blood pressure. If this does not happen, or happens too slowly, postural hypotension results.

The risk of both low and high blood pressure normally increases with age due in part to normal changes during aging. In addition, blood flow to the heart muscle and the brain declines with age, often as a result of plaque buildup in blood vessels. An estimated 10% to 20% of people over age 65 have postural hypotension.

This answer should not be considered medical advice...down arrowThis answer should not be considered medical advice and should not take the place of a doctor’s visit. Please see the bottom of the page for more information or visit our Terms and Conditions.up arrow

Posted:
| Report This Report Answer
Archived: March 20, 2014

Was this helpful?

YesNo

Thanks for your feedback.

2703 of 2916 found this helpful
Read the Original Article: Understanding Low Blood Pressure -- the Basics

Answers from Contributors (1)