What are typical symptoms of hypoxia, and how can it be prevented in flight?

• A. Headache, dizziness, impaired judgment; prevent by using supplemental oxygen when required and by descending.
• B. Nausea only; prevent by hydration.
• C. Euphoria; prevent by increased altitude.
• D. Fever; prevent by rest.

Answer: (A)

Hypoxia is when the body's tissues don't get enough oxygen, which is a real concern at altitude because the partial pressure of oxygen is lower in the air we breathe. The most common early signs you’ll notice are headache, dizziness, and impaired judgment—these reflect the brain not getting enough oxygen and can quickly degrade your ability to fly safely.

Prevention centers on keeping the oxygen supply adequate and reducing altitude if you start to feel symptoms. Use supplemental oxygen as required and descend to a lower altitude to restore normal oxygen levels. These steps help prevent the progression of hypoxia and maintain safe pilot performance.

Nausea is not the typical hallmark of hypoxia in flight, and euphoria or attempting to “fix” it by increasing altitude would worsen the problem. Fever isn’t related to hypoxia in this context, and resting doesn’t address the oxygen deficit.