High carbon dioxide: Back in medical school, it was explained to me that as we get tired our respiratory rate goes down raising our carbon dioxide level. This rise causes us to yawn and take a deep breath to expel the rising carbon dioxide. It sounded good to me at the time.
Answered 4/8/2018
6.1k views
90,000 U.S. doctors in 147 specialties are here to answer your questions or offer you advice, prescriptions, and more.
Ask your question