Understanding the 10 Symptoms of High Altitude Sickness

10. Coughing Up Blood

When the lungs are filling with fluid as a result of altitude sickness, the person may cough up bloody mucus or foam in an attempt to clear space for breathing. This is a sign that an individual requires emergency attention, both to transport him or her to a lower altitude and to address the fluid in the lungs. Rescue personnel should also look for any other ways compromised bodily functions, as exhibited by confusion or weakness.

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