The Food and Drug Administration is moving to tighten expectations for pulse oximeter testing, a step aimed at improving the accuracy of devices used to estimate blood oxygen levels across a wider range of patients.
The agency’s draft guidance, released in January 2025, focuses on pulse oximeters used for medical purposes and recommends changes to how manufacturers evaluate device performance before seeking clearance. The issue has drawn increased attention since the COVID-19 pandemic, when pulse oximeters became familiar household devices and concerns grew that readings could be less reliable for some patients, including people with darker skin pigmentation.
Pulse oximeters estimate the percentage of oxygen-saturated hemoglobin in the blood by passing light through tissue, usually a fingertip. The number shown on the device, known as oxygen saturation, can help clinicians assess whether a person may be having trouble getting enough oxygen. But the FDA has warned that pulse oximeters have limitations and that readings should be interpreted in context rather than treated as a stand-alone diagnosis.
The agency’s latest draft guidance is not a ban on existing devices or a warning against using pulse oximeters. Instead, it is an attempt to improve how devices are studied, labeled and submitted for regulatory review. According to the FDA announcement, the updated recommendations are intended to help generate a more representative study of the intended population for these devices.
Under the FDA’s proposed recommendations, manufacturers would be expected to include a more representative range of skin pigmentation in clinical testing. The agency said the goal is to better evaluate how devices perform across the intended patient population. That would mark a shift from older testing approaches that critics say did not adequately capture differences in accuracy among patients.
For consumers, the immediate takeaway is more practical than technical: a pulse oximeter reading can be useful, but it is not perfect. Factors such as poor circulation, cold hands, nail polish, artificial nails, skin thickness, tobacco use and ambient light may affect performance. Skin pigmentation has also been identified as a factor that can influence accuracy.
Health professionals generally advise patients to pay attention not only to the number on the screen, but also to symptoms such as shortness of breath, chest pain, bluish lips, confusion or worsening fatigue. A normal-looking reading should not override concerning symptoms, and a low or unexpected reading should be checked carefully and, when appropriate, discussed with a clinician.
The issue is especially important because pulse oximeters are used in hospitals, clinics and homes. They can guide decisions about respiratory illness, chronic lung disease, sleep-related breathing problems and recovery from infection. If a device overestimates oxygen levels in some patients, clinicians may miss early signs of deterioration.
The FDA’s draft guidance still must go through the agency’s review process before finalization. But the direction is clear: oxygen monitoring is becoming a health equity issue as well as a device-performance issue.
For The Breathing Report reader, the practical message is simple. Pulse oximeters can be helpful tools, especially when used consistently and in consultation with a medical professional. But they should be treated as one piece of information—not the final word on how well someone is breathing.
Sources: FDA pulse oximeter draft guidance announcement; Reuters coverage of FDA proposal
