Which of the following are symptoms of advanced hypoxia?

• A. Headaches, tiredness, blurred vision, loss of muscular coordination, and personality changes
• B. Nausea and vomiting
• C. Sneezing and runny nose
• D. Cough and fever

Answer: (A)

Advanced hypoxia causes the brain to lose oxygen more severely, so signs shift from general fatigue to clear neurological and coordination problems. When oxygen delivery is critically low, headaches emerge from the brain’s stress, and tiredness reflects the energy gap in brain cells. Blurred vision happens because visual processing becomes unreliable under low oxygen. Loss of muscular coordination, or ataxia, points to cerebellar involvement, while personality changes show higher brain areas struggling to function. Taken together, these symptoms reveal a late, more dangerous stage of hypoxia that demands immediate corrective action, such as descending and increasing oxygen.

Nausea and vomiting can occur with altitude illness but aren’t the hallmark indicators of advanced hypoxia. Sneezing and runny nose are not related to oxygen deprivation, and cough with fever suggests an infection rather than pure hypoxia.