Skip to main content
Aviation glossary

Hyperventilation

What is hyperventilation?

Illustration related to hyperventilation
Image: http://www.scientificanimations.com — CC BY-SA 4.0, via Wikimedia Commons

Hyperventilation is breathing too fast or too deeply, which flushes out an excessive amount of carbon dioxide from the blood and raises blood pH, leading to symptoms like dizziness, tingling, and muscle spasms. Unlike hypoxia—which causes cyanosis (a bluish skin color) and limp muscles—hyperventilation produces a pale, clammy appearance and muscle tension. It is often triggered by stress, fear, or anxiety, and the cure is to restore normal carbon dioxide levels by slowing your breathing rate (such as talking aloud or breathing into a bag). Think of it as "blowing off too much CO2"—calm down and slow your breathing to recover.

Studying for an FAA written test?

Terms like hyperventilation show up on the FAA knowledge test. Study them in context with ACS-aligned practice questions, AI explanations, and the cited FAA handbook reference behind every answer — free to start.

Learn more in the library

Related terms

Browse the full glossary →