Tachycardia refers to a heart rate that’s too fast. How that’s defined may depend on your age and physical condition. Generally speaking, for adults, a heart rate of more than 100 beats per minute (BPM) is considered too fast. View an animation of tachycardia. If your resting pulse tends to be between 100 and 105, there are things you can do to lower it, but you’ll probably need some patience; don’t expect the lowering to occur overnight. First off, stop smoking if you smoke. Smoking accelerates resting pulse. A normal resting heart rate for adults is (2) between 60 beats per minute (bpm) and 100 bpm. An abnormal pulse rate below 60 bpm or above 100 bpm could increase your risk of cardiovascular disease, stroke, or early death. Normal Resting Heart Rate for Women. If a person's heart rate is consistently over 100 beats per minute, the person is considered to have a high heart rate, which is also known as tachycardia. Although tachycardia is considered relatively harmless, it can decrease the efficiency of the heart by lowering. Pulse of 100 is bordering on tachycardia (fast heart rate) but may be anticipated with marked anxiety. 3 doctors agree Send thanks to the doctor 90,000 U.S. Doctors in 147 specialties are here to answer your questions or offer you advice, prescriptions, and more.

Elevated Heart Rate Most Likely Caused by Medical Condition

May 6, 2011

Dear Mayo Clinic:

What is sinus tachycardia? What causes it? How is it treated?

Answer:

Sinus tachycardia is the term used to describe a faster-than-normal heartbeat — a rate of more than 100 beats per minute versus the typical normal of 60 to 70 beats per minute. Well over 99 percent of the time, sinus tachycardia is perfectly normal. The increased heart rate doesn't harm the heart and doesn't require medical treatment.

The term sinus tachycardia has nothing to do with sinuses around the nose and cheeks. Rather, it comes from the sinus node, a thumbnail-sized structure in the upper right chamber of the heart. This structure controls the heart rate and is called the heart's natural pacemaker.

The sinus node signals the heart to speed up during exercise or in situations that are stressful, frightening or exciting. For example, a 10- to 15-minute brisk walk typically elevates the heart rate to 110 to 120 beats per minute. Also, the sinus node increases the heart rate when the body is stressed because of illness. In all of these circumstances, the heart rate increase is a normal response.

Likewise, the sinus node signals the heart to slow down during rest or relaxation.

We see patients who are concerned because their heart rate stays elevated in the range of 100 to 130 beats per minute. Almost always, there is a medical reason that the sinus node keeps signaling for the faster rate. Possibilities include anemia, an underlying infection, elevated thyroid hormone, or reaction to medication. Addressing those conditions would likely bring the heart rate back to a normal rate. Other factors may be involved, too, such as overdoing caffeine. For example, I saw one patient who was eating several chocolate bars a day. The caffeine in the chocolate was elevating her heart rate.

Rarely, the sinus node can jump-start the heart rate with no apparent cause — no stress, illness or high activity level. This is termed inappropriate sinus tachycardia. About half of the time, this phenomenon occurs after recovery from a serious illness, usually a viral illness. And most often, those affected are women in their 20s and 30s.

Inappropriate sinus tachycardia doesn't cause heart damage, though patients may feel uncomfortable with the elevated heart rate. Some patients may have other associated symptoms such as fatigue, headache, chest discomfort, shortness of breath or light-headedness. When symptoms are problematic, treatment can include beta blockers that block the action of adrenaline and help slow the heart rate. Very rarely, the heart may maintain very high rates of 160 to 180 beats per minute. More involved treatment options are available to control this condition.

For some patients, the elevated heart rate is the only symptom. Some have a lifelong history of sinus tachycardia in the 110 beats per minute range, and they lead a normal, healthy life. And often the inappropriate sinus tachycardia will improve in time without treatment.

We encourage patients with prolonged sinus tachycardia to improve their overall fitness level. The more fit you are, the lower your resting heart rate. The elevated heart rate could slow with improved conditioning.

Patients who have concerns about an elevated heart rate should check with their physician. Other conditions, such as atrial fibrillation, can cause a racing heart. Atrial fibrillation should be treated, as it increases the risk of stroke and can damage the heart.

— Stephen Hammill, M.D., Cardiology, Mayo Clinic, Rochester, Minn.

Date Issued: February 19, 2021

The Coronavirus Disease 2019 (COVID-19) pandemic has caused an increase in the use of pulse oximeters, and a recent report (Sjoding et al.) 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.

Recommendations for Patients and Caregivers

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.

For more consumer information on pulse oximeters, see Pulse Oximeters and Oxygen Concentrators: What to Know About At-Home Oxygen Therapy.

Recommendations for Health Care Providers

• 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. Review the information in the sections below to better understand how accuracy is calculated and interpreted.
• Refer to the device labeling or the manufacturer’s website to understand the accuracy of a particular brand of pulse oximeter and sensor. Different brands of pulse oximeters and even different sensors (finger clip versus adhesive) may have a different accuracy level. Pulse oximeters are least accurate when oxygen saturations are less than 80%.
• Consider accuracy limitations when using the pulse oximeter to assist in diagnosis and treatment decisions.
  • Use pulse oximeter readings as an estimate of blood oxygen saturation. For example, a pulse oximeter saturation of 90% may represent an arterial blood saturation of 86-94%.
  • When possible, make diagnosis and treatment decisions based on trends in pulse oximeter readings over time, rather than absolute thresholds.

Device Description

A pulse oximeter is a device that is usually placed on a fingertip. It uses light beams to estimate the oxygen saturation of the blood and the pulse rate. Oxygen saturation gives information about the amount of oxygen carried in the blood. The pulse oximeter can estimate the amount of oxygen in the blood without having to draw a blood sample.

Most pulse oximeters show two or three numbers. The most important number, oxygen saturation level, is usually abbreviated SpO₂, and is presented as a percentage. The pulse rate (similar to heart rate) is abbreviated PR, and sometimes there is a third number for strength of the signal. Oxygen saturation values are between 95% and 100% for most healthy individuals, but sometimes can be lower in people with lung problems. Oxygen saturation levels are also generally slightly lower for those living at higher altitudes.

There are two categories of pulse oximeters: prescription use and over the counter (OTC).

• Prescription oximeters are reviewed by the FDA, receive 510(k) clearance, and are available only with a prescription. The FDA requires that these pulse oximeters undergo clinical testing to confirm their accuracy. They are most often used in hospitals and doctors’ offices, although they may sometimes be prescribed for home use.
• Over-the-counter (OTC) oximeters are sold directly to consumers in stores or online and include smart phone apps developed for the purpose of estimating oxygen saturation. Use of OTC oximeters has increased as a result of the COVID-19 pandemic. These products are sold as either general wellness or sporting/aviation products that are not intended for medical purposes, so they do not undergo FDA review. OTC oximeters are not cleared by the FDA and should not be used for medical purposes.

For more information on pulse oximeter regulation, see Pulse Oximeters - Premarket Notification Submissions [510(k)s]: Guidance for Industry and Food and Drug Administration Staff.

Interpretation and Limitations of Pulse Oximetry

Pulse oximeters have limitations and a risk of inaccuracy under certain circumstances. In many cases, the level of inaccuracy may be small and not clinically meaningful; however, there is a risk that an inaccurate measurement may result in unrecognized low oxygen saturation levels. Therefore, it is important to understand the limitations of pulse oximetry and how accuracy is calculated and interpreted.

FDA-cleared prescription pulse oximeters are required to have a minimum average (mean) accuracy that is demonstrated by desaturation studies done on healthy patients. This testing compares the pulse oximeter saturation readings to arterial blood gas saturation readings for values between 70-100%. The typical accuracy (reported as Accuracy Root Mean Square or A_rms) of recently FDA-cleared pulse oximeters is within 2 to 3% of arterial blood gas values. This generally means that during testing, about 66% of SpO₂ values were within 2 or 3% of blood gas values and about 95% of SpO₂ values were within 4 to 6% of blood gas values, respectively.

However, real-world accuracy may differ from accuracy in the lab setting. While reported accuracy is an average of all patients in the test sample, there are individual variations among patients. The SpO₂ reading should always be considered an estimate of oxygen saturation. For example, if an FDA-cleared pulse oximeter reads 90%, then the true oxygen saturation in the blood is generally between 86-94%. Pulse oximeter accuracy is highest at saturations of 90-100%, intermediate at 80-90%, and lowest below 80%. Due to accuracy limitations at the individual level, SpO₂ provides more utility for trends over time instead of absolute thresholds. Additionally, the FDA only reviews the accuracy of prescription use oximeters, not OTC oximeters meant for general wellness or sporting/aviation purposes.

Many patient factors may also affect the accuracy of the measurement. The most current scientific evidence shows that there are some accuracy differences in pulse oximeters between dark and light skin pigmentation; this difference is typically small at saturations above 80% and greater when saturations are less than 80%. In the recently published correspondence by Sjoding, et. al., the authors reported that Black patients had nearly three times the frequency of occult hypoxemia (low oxygen levels in the blood) as detected by blood gas measurements but not detected by pulse oximetry, when compared to White patients. It is important to note that this retrospective study had some limitations. It relied on previously collected health record data from hospital inpatient stays and could not statistically correct for all potentially important confounding factors. However, the FDA agrees that these findings highlight a need to further evaluate and understand the association between skin pigmentation and oximeter accuracy.

All premarket submissions for prescription use oximeters are reviewed by the FDA to ensure that clinical study samples are demographically representative of the U.S. population, as recommended by FDA guidance, Pulse Oximeters - Premarket Notification Submissions [510(k)s]: Guidance for Industry and Food and Drug Administration Staff. As described in this guidance, FDA recommends that every clinical study have participants with a range of skin pigmentations, including at least 2 darkly pigmented participants or 15% of the participant pool, whichever is larger. Although these clinical studies are not statistically powered to detect differences in accuracy between demographic groups, the FDA has continued to review the effects of skin pigmentation on the accuracy of these devices, including data from controlled laboratory studies and data from real world settings.

FDA Actions

The FDA is committed to the continued evaluation of the safety, effectiveness, and availability of medical devices, especially devices in high demand during the COVID-19 pandemic. The FDA is evaluating published literature pertaining to factors that may affect pulse oximeter accuracy and performance, with a focus on literature that evaluates whether products may be less accurate in individuals with darker skin pigmentation. The FDA has been working on additional analysis of premarket data, as well as working with outside stakeholders, including manufacturers and testing laboratories, to analyze additional postmarket data to better understand how different factors including skin pigmentation may affect pulse oximeter accuracy. Based on these findings, the FDA may reassess the content of the pulse oximetry guidance document.

The FDA will keep the public informed if significant new information becomes available.

Pulse Over 100 Means

Reporting Problems with a Pulse Oximeter

If you think you have a problem with a pulse oximeter, the FDA encourages you to report the problem through the MedWatch Voluntary Reporting Form.

Fast Pulse Rate Meaning

Health care personnel employed by facilities that are subject to the FDA's user facility reporting requirements should follow the reporting procedures established by their facilities.

Pulse Over 100 At Rest In Elderly

Questions?

What Does A High Heart Rate Mean

If you have questions, email the Division of Industry and Consumer Education (DICE) at DICE@FDA.HHS.GOV or call 800-638-2041 or 301-796-7100.