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Symptoms of Fainting
A faint is characterised by suddenly feeling weak and unsteady, before passing out for a short period of time, usually just for a few seconds. It can happen when you are sitting down, standing up, or when you get up too quickly, and is caused by a momentary shortage of oxygen to the brain. Fainting is your body’s way of getting you to lie down, so that oxygen-carrying blood can quickly get back to your brain.
Just before you lose consciousness, you may experience the following symptoms:
- yawning;
- a sudden clammy sweat;
- nausea;
- fast, deep breathing;
- confusion;
- blurred vision or ‘spots’ in front of the eyes; and
- ringing in the ears.
This is followed by loss of strength and loss of consciousness. It takes only a few seconds for this sequence to run, and there may be very little warning before a person collapses.
By collapsing to the ground, your head and heart are on the same level. This means your heart does not have to work as hard to push blood up to the brain, and you should return to consciousness after a few seconds. It is common to feel confused and weak for 20–30 minutes after fainting.
If you already feel unwell, you may be more likely to faint. People who are otherwise healthy can also faint suddenly and unexpectedly.
