R55: Syncope and collapse

Insufficient blood reaching the brain for a short time causes you to become unconscious. There are a number of reasons why you can lose consciousness. Many of them are not dangerous.

Normally, the body adjusts the heartbeat and the width of the blood vessels to the situation. Sometimes the body cannot adjust to the situation properly. This causes you to lose consciousness. This can happen if you stand for a long time or experience emotional distress.

You can also pass out if the heart can no longer pump enough blood into the body. This can happen when the heart is beating much too slowly or too quickly. You may also pass out if the heart is beating irregularly. A heart valve that has stopped working can be another reason.

You can also pass out if the brain doesn’t get enough blood when you change position. Changing position is when you stand up too quickly, for example.

You can also pass out if you don’t have enough fluid in the body.

Patient Disclaimer

The information provided on this page is for general educational purposes only. It is not intended for self-diagnosis and does not replace professional medical advice. Always consult your doctor or a qualified healthcare provider with any questions or concerns about your health.

If you see an ICD diagnosis code (e.g., on a medical report), be aware that doctors may also include additional indicators to express diagnostic certainty. Only a healthcare professional can interpret these codes accurately in the context of your individual case.

For a complete understanding of your condition and what the diagnosis means for you, please speak directly with your doctor.