Healthwise
To print: Use your web browser's print feature. Close this window after printing.

Blood Pressure Numbers: When to Get Help

Table of Contents


Overview

What do your blood pressure numbers mean?

Blood pressure is a measure of the force of blood against the walls of your arteries. Blood pressure readings include two numbers. The first number is the systolic pressure (top number). This is the force of blood on the artery walls as your heart pumps. The second number is the diastolic pressure (bottom number). This is the force of blood on the artery walls between heartbeats.

If the top number stays high, or the bottom number stays high, or both, that means you have high blood pressure (hypertension). It's normal for blood pressure to go up and down throughout the day. Your doctor will give you a goal for your blood pressure.

What can cause blood pressure to go up or down?

It's normal for blood pressure to go up and down throughout the day. Things like exercise, stress, and sleeping can affect your blood pressure. Some medicines can cause your blood pressure to go up. These medicines include certain asthma medicines and cold remedies.

A low blood pressure reading can be caused by many things, including some medicines, a severe allergic reaction, or an infection. Another cause is dehydration, which is when your body loses too much fluid.

When should you call your doctor?

One high or low blood pressure reading by itself may not mean you need to call for help. If you take your blood pressure and it is out of the normal range, wait a few minutes and take it again. If it's still high or low, use the following guidance.

Call 911 anytime you think you may need emergency care. For example, call if:

Call your doctor now or seek immediate medical care if:

Watch closely for changes in your health, and be sure to contact your doctor if:


Credits for Blood Pressure Numbers: When to Get Help

Current as of: November 9, 2022

Author: Healthwise Staff
Medical Review:
E. Gregory Thompson MD - Internal Medicine
Martin J. Gabica MD - Family Medicine
Adam Husney MD - Family Medicine


Note: The "printer friendly" document will not contain all the information available in the online document. Some information (e.g. cross-references to other topics, definitions or medical illustrations) is only available in the online version.

© 1995-2023 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.