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If you’ve ever had that light-headed feeling after standing up too fast, you know how unpleasant and alarming it can be.

If you’ve ever had that light-headed feeling after standing up too fast, you know how unpleasant and alarming it can be. You feel a little dizzy, your vision narrows, blurs or greys out, and you may feel a little sick to your stomach. Some people experience it more frequently than others, but it can happen to anyone at any time. 


Depending on what causes you to feel like you’re about to faint, it may not be a long-term problem or it could be a symptom of a medical condition that requires treatment. In either case, you should talk to your doctor as soon as possible if you feel faint or actually lose consciousness.

“The feeling that you’re about to faint is called presyncope,” says Lia F. Crispell, certified registered nurse practitioner at ConvenientCare in Pittston. “It happens when the brain doesn’t get enough blood, oxygen or glucose to function properly, even momentarily.”

The common causes of presyncope

“People who experience presyncope usually dismiss it and move on with their day,” says Crispell. “This isn’t a good idea since some of the causes can be serious. It’s always best to get a diagnosis from a doctor.” 


The potential causes of presyncope include:


  • Orthostatic hypotension: Also called postural hypotension, this is the head rush you sometimes feel when you stand up. It’s caused when blood pools in the blood vessels for too long and your heart doesn’t have enough blood to pump to your brain. It can happen to anyone, and more frequently if you’re taking certain medications and as you age.
  • Heart arrhythmia: Also known as an abnormal heart rate, this condition can cause your heart to beat too fast, too slow, or in a way that causes a sudden decrease in the blood supply to your brain. This can make you feel faint.
  • Medications: Medicines prescribed for pain, heart conditions and high blood pressure have the potential to affect your circulatory system in different ways that can lead to feeling faint. If this happens frequently, you should talk to your doctor about adjusting your dosage.
  • Dehydration: Not consuming enough fluids can cause nausea, weakness, dizziness, low blood pressure and fainting. Rehydrating will help to alleviate these symptoms quickly.
  • Anemia: Anemia is a condition that causes a lack of healthy red blood cells or hemoglobin in your blood, which carry oxygen to your organs – including your brain. The hallmark of anemia is tiredness, but it can also cause sufferers to feel faint and dizzy.
  • Autonomic neuropathy: This nerve disease disrupts electrical signals between the brain and the heart, blood vessels, and sweat glands. It can affect heart rate and blood pressure.
  • Stress and panic attacks: Anxiety can cause sufferers to breathe more rapidly and deeply, which can lead to lightheadedness and dizziness.


What to do if you feel faint

“The most important thing to do if you feel faint is to get to a safe place,” says Crispell. “If you faint, you’ll eventually regain consciousness, but there is a chance you’ll be injured by falling or bumping your head.”

If you feel faint, lie down or sit down and place your head between your knees. If you’re with someone who complains about feeling faint, advise them to do the same.

After the fainting spell passes, it’s important to contact your healthcare provider as soon as possible for a checkup. Only a trained medical professional will be able to pinpoint the exact cause of presyncope.

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Meet Lia Crispell, CRNP

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