What Happens In Your Body When You Faint?

Fainting (also called syncope) occurs when your brain isn’t getting enough oxygen or nutrients. It could be due to an overreaction of the parasympathetic nervous system. This system in the body normally calms the body down by reducing blood pressure, heart rate, and breathing.

Occasional fainting is usually nothing to worry about, but you should talk to a doctor if it happens often or lasts more than a few minutes. There are some cases of more serious conditions that need to be addressed. Your doctor can run some tests and treat the underlying conditions causing you to faint.

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Written by:

Hilary Weissman

Hilary Weissman has been a health writer for the past 6 years. She was a senior copywriter at WW (Weight Watchers) before joining GoodRx and was also a copy editor in S&P Global’s structured finance ratings group for 3 years prior.

Reviewed by:

Sanjai Sinha, MD

Sanjai Sinha, MD, is a board-certified physician with over 20 years of experience. He specializes in internal medicine.

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