Before taking your blood pressure

• Find a quiet place.

• Check to be sure you have the correct size cuff. If you are not sure, or if you have questions, talk to your healthcare provider. (Avoid wrist and finger monitors to ensure an accurate blood pressure reading.)

• Roll up the sleeve on your left arm or remove any tight-sleeved clothing, if needed. (It's best to take your blood pressure from your left arm if you are right-handed. However, you can use the other arm if you have been told to do so by your healthcare provider.)

• Rest in a chair next to a table for 5 to 10 minutes. (Your left arm should rest comfortably at heart level.)

• Sit up straight with your back against the chair, legs uncrossed and on the ground.

• Rest your forearm on the table with the palm of your hand facing up.

• You should not talk, read the newspaper, or watch television during this process.

Taking your blood pressure

If you buy a manual or digital blood pressure monitor (sphygmomanometer), follow the instruction booklet carefully.

Record your blood pressure

If you have been asked to record your blood pressure and bring your readings to the office, please write down the date, time of day, systolic and diastolic numbers, heart rate, and which arm you took the reading on. If you are taking part in a program that has remote monitoring, your blood pressure readings are automatically shared with your medical provider. If you are unsure, please ask your provider.

Pulse Oximeter Accuracy

The Coronavirus Disease 2019 (COVID-19) pandemic has caused an increase in the use of pulse oximeters, and a recent report (Sjoding et al.External Link Disclaimer) suggests that the devices may be less accurate in people with dark skin pigmentation. The U.S. Food and Drug Administration (FDA) is informing patients and health care providers that although pulse oximetry is useful for estimating blood oxygen levels, pulse oximeters have limitations and a risk of inaccuracy under certain circumstances that should be considered. Patients with conditions such as COVID-19 who monitor their condition at home should pay attention to all signs and symptoms of their condition and communicate any concerns to their health care provider.

How to take a reading:

• Follow your health care provider’s recommendations about when and how often to check your oxygen levels.

• Be aware that multiple factors can affect the accuracy of a pulse oximeter reading, such as poor circulation, skin pigmentation, skin thickness, skin temperature, current tobacco use, and use of fingernail polish. To get the best reading from a pulse oximeter:

  • Follow the manufacturer’s instructions for use.

  • When placing the oximeter on your finger, make sure your hand is warm, relaxed, and held below the level of the heart. Remove any fingernail polish on that finger.

  • Sit still and do not move the part of your body where the pulse oximeter is located.

  • Wait a few seconds until the reading stops changing and displays one steady number.

• Write down your oxygen levels with the date and time of the reading so you can easily track changes and report these to your health care provider.

How to interpret a reading:

• When taking pulse oximeter measurements, pay attention to whether the oxygen level is lower than earlier measurements, or is decreasing over time. Changes or trends in measurements may be more meaningful than one single measurement. Over the counter products that you can buy at the store or online are not intended for medical purposes.

• Do not rely only on a pulse oximeter to assess your health condition or oxygen level.

• If monitoring oxygen levels at home, pay attention to other signs or symptoms of low oxygen levels, such as:

  • Bluish coloring in the face, lips, or nails;

  • Shortness of breath, difficulty breathing, or a cough that gets worse;

  • Restlessness and discomfort;

  • Chest pain or tightness; and

  • Fast or racing pulse rate.

  • Be aware that some patients with low oxygen levels may not show any or all of these symptoms. Only a health care provider can diagnose a medical condition such as hypoxia (low oxygen levels).

When to contact your health care provider:

• If you are concerned about the pulse oximeter reading, or if your symptoms are serious or getting worse, contact a health care provider.

• If you think you may have COVID-19, contact your health care provider or local health department about getting a diagnostic test for COVID-19. Pulse oximeters cannot be used to diagnose or rule out COVID-19.