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Hyperventilation

Dr Lynn Thomas, OStJ, BSc, MB.BS, MA, FRCPClinically reviewed: 28/04/2025

Find out what to do if someone is hyperventilating.

What is hyperventilation?

Hyperventilation is unnatural, fast, or deep breathing, normally caused by anxiety, experiencing an emotional upset, or a history of panic attacks.

Signs and symptoms

Look for:

  • abnormally fast or deep breathing

  • anxiety

  • a rapid pulse.

Later they may develop:

  • dizziness or feeling faint

  • trembling, sweating, and dry mouth

  • tingling and cramps in hands, feet, and around the mouth.

What to do

  1. 1

    Try to reassure the casualty and be kind. If you can, take them to a quiet place. This may help them to regain control of their breathing. Ask any bystanders to leave. Give the casualty space.

    • Do not advise the casualty to breathe into a paper bag as this could make the condition worse.

  2. 2

    Encourage them to seek medical advice, so they can learn how to prevent and control hyperventilation or a panic attack in the future.

    • It is rare for children to suffer from hyperventilation, so you should try looking for other causes.

    • If you are worried, and they do not seem to improve, call 999 or 112 for emergency help.

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