Fainting and passing out are the same thing, both referring to the medical term syncope: a temporary loss of consciousness and muscle tone due to a sudden drop in blood flow to the brain, causing a brief collapse and quick recovery (usually under a minute). While often harmless (like dehydration or heat), it can signal serious issues like heart problems, so recurring or unexplained episodes need medical attention to rule out severe underlying conditions like heart attack, stroke, or seizures.
Syncope (SINK-a-pee) is another word for fainting or passing out. Someone is considered to have syncope if they become unconscious and go limp, then soon recover. For most people, syncope occurs once in a great while, if ever, and is not a sign of serious illness.
However, it may be indicative of underlying health conditions, such as low blood pressure, abnormal heart rhythm, hypoglycemia or stress, so the person should seek follow-up medical attention. If someone faints or appears to be fainting, call 911 or your local emergency number.
Types of Syncope
There are several types of syncope. The most common type in children is called vasovagal syncope, which is a benign type of fainting that occurs in response to a trigger, such as pain or emotional stress. Orthostatic hypotension is another type of benign syncope that can occur in children.
The average age of the first fainting is about 14 years, and most people with VVS experience their first fainting before age 40 [10]. VVS seems to show a bimodal age distribution with a peak in adolescence and after 60 years of age [20].
Doctors start by doing a complete physical exam and taking a medical history. In kids and teens, POTS causes a heart rate increase of 40 or more beats per minute within 10 minutes of when they move from a supine (lying down) position to a standing one.
Bad signs after fainting (syncope) needing immediate medical help include chest pain, shortness of breath, irregular heartbeat, slurred speech, seizure-like jerking, severe injury from the fall, losing bladder/bowel control, fainting while lying down or exercising, prolonged confusion, or fainting more than once, as these can signal serious heart or brain issues, not just a simple faint. Seek emergency care if there are no warning signs or if you're over 50, pregnant, or have diabetes.
there are features suggestive of uncomplicated faint (the 3 'P's) such as: Posture – prolonged standing, or similar episodes that have been prevented by lying down. Provoking factors (such as pain or a medical procedure) Prodromal symptoms (such as sweating or feeling warm/hot before TLoC).
Fainting and seizures can be confused because they sometimes share similar symptoms: Convulsive syncope: It is estimated that between 6% and 25% of of people with the most common kind of syncope (vasovagal syncope) have convulsions. To the untrained eye, this may look like an epileptic seizure.
Diagnostic workup for syncope requires a thorough history, physical exam, and a 12-lead ECG. Cardiac monitoring is necessary in patients that present to ER with an acute presentation of syncope, and a strong suspicion for cardiac etiology2.
Your eyes will usually stay open.
Fainting is when you pass out for a short time. It's not usually a sign of something serious, but if it happens you should see a GP.
Before you faint, it is common to get warning signs such as weakness, dizziness, nausea, vision changes or anxiety. A faint can be caused by tiredness, dehydration, severe pain, anxiety, low blood pressure, low blood sugar levels, heart attack or stroke.
Fainting spells can sometimes be the first warning sign of an undiagnosed heart disease. Heart conditions associated with fainting can include: Arrhythmia, or irregular heartbeat, including bradycardia (too slow) or tachycardia (too fast) Structural heart defects.
Always contact your doctor for a check-up after your first fainting episode. They'll usually do a blood test to look at electrolytes and kidney function as well as perform an electrocardiogram and blood pressure check. Based on your medical history, your doctor may choose to order additional tests or imaging, too.
These conditions can include: abnormal heart rhythm (arrhythmia), blood clot, heart valve disease or heart failure. Neurologic syncope comes from an issue in your brain that limits blood flow there. It can happen when you have a neurological condition like a seizure, stroke or transient ischemic attack (TIA).
Dizziness (light-headed), blurred vision, nausea, sweating, feeling cold. These last for 5 to 10 seconds before passing out. The person may look pale just before passing out.
If someone else faints
Prop up the person's legs about 12 inches (30 centimeters). Loosen belts, collars or other tight clothing. To reduce the chance of fainting again, don't get the person up too fast. If the person doesn't regain consciousness within one minute, call 911 or your local emergency number.
Your nervous system controls everything in your body, including blood pressure. If something goes wrong, your blood pressure can suddenly drop, reducing oxygen to the brain and causing you to faint. This can happen for various reasons, including nerve-related conditions.
Most often, there is a warning prodrome, consisting of nausea, sweating, pallor, feeling of warmth, tingling of extremities, “graying out” and/or tunnel vision.
Although most strokes do not cause fainting, a stroke or transient ischemic attack (TIA) that involves certain blood vessels at the base of the brain (posterior circulation stroke) can cause fainting. Similarly, a migraine that involves these blood vessels sometimes causes fainting.
POTS (Postural Orthostatic Tachycardia Syndrome) most commonly begins in teenagers and young adults, especially females, often between ages 15 and 25, with many cases starting around puberty or following triggers like viral infections, pregnancy, trauma, or surgery. While it can affect any age, early adolescence (around 12-15) is a peak time for symptom onset, with a significant portion starting after a specific stressful event, say National Institute of Neurological Disorders and Stroke and National Institutes of Health (NIH) | (.gov).
Referral to cardiology is always recommended for the following red-flag symptoms: Syncope during exercise or any physical exertion. Absence of a prodrome or no warning signs preceding the episode. Prolonged loss of consciousness or reports of being unresponsive for an extended period of time.
Common differential diagnoses for POTS include thyroid disorders and thyrotoxicosis, inappropriate sinus tachycardia, pheochromocytoma, anxiety, dehydration, infection, hypoadrenalism, and medication-induced tachycardia.