 [ Symptoms ] what causes high fever sores on lips and in mouth general malaise patient is 15 years and has been treated 9 days patient began with sore throat and fever which quickly shot to 103  104 he was taken to emergency room and the diagnosis was possible hand foot and mouth but no sores on his hands or feet he has been treated with azithromax for 9 days now and the fever is subsiding but the sores on and in his mouth gums tongue and back of throat are raw open oozing and very painful he still is unable to eat no more than milkshakes gator aid also the smell is becoming bad like rotten meat [ Disease ] many things can cause low oxygen levels in the blood to name a few lung injury  collapsed lung  lung disease  copd lung cancer  pulmonary embolism  heart disease  congestive heart failure  anemias    and that is just a handful i can think of off the top of my head this is why your doctor wants you to go in for further testing which i recommend you do as soon as possible low blood oxygen levels are nothing to mess around with obviously all of your organs including your heart require adequate amounts of oxygen to function properly in answer to your question the corrective action for low oxygen levels will vary depending on the underlying problem in the meantime you can help your body get as much oxygen as possible by sleeping with your head elevated on a couple of pillows and by pausing to take 3 or 4 slow deep breaths every hour when you are awake keyword slow  with luck the source of your low oxygen levels will be diagnosed quickly and turn out to be something easily treatable that is my wish for you all the best lack of oxygen in the artery blood what causes low oxygen levels in a person who has osteoporosis