Doctors can now smell physical pain in a patient's breath by detecting a specific metabolic signature that appears when they are hurting.

Pain is famously difficult to measure because it relies entirely on a patient's subjective report. Researchers have identified a specific set of metabolic shifts that show up in exhaled breath the moment a person experiences pain. Using this signature, they were able to accurately identify pain states with a high degree of precision. This objective pain meter could revolutionize how we treat babies, people with dementia, or patients in comas who cannot speak for themselves. It takes the guesswork out of pain management and ensures that patients receive the right amount of medication exactly when they need it.