Syncope symptoms are signs that you may have a condition that causes the heart to stop pumping enough blood to your brain. It can be a harmless or life-threatening problem.
Your doctor will ask about the symptoms you are having, and if you have ever fainted before. These symptoms include a change in your sense of balance or hearing, a visual “gray out” (when you can’t see anything well), sudden weakness or sweating and a feeling of “being slowed down.”
The first thing your doctor will do is look at your medical history and do a physical exam. This will include measuring your heart rate and blood pressure when you’re lying down, seated and standing. It will also include doing an electrocardiogram (ECG) to check your heart’s rhythm.
Sometimes the cause of syncope is a non-life-threatening problem like a mild case of dehydration or a muscle strain. If the problem is a serious one like a blockage in your arteries or a heart-valve problem, your doctor may recommend medicine or a pacemaker.
Fainting occurs when there is not enough oxygen flowing to your brain, because the blood vessels in your legs widen and drop your heart rate (this is called vasovagal syncope). You can avoid fainting by staying out of hot places and not standing for long periods. If you have an episode of vasovagal syncope, try to lie down right away and raise your legs in the air until you feel better.

Vasovagal syncope is the most common type of reflex syncope, occurring in about one-third of people. It’s usually caused by a combination of dehydration and upright posture, but it can be triggered by strong emotions (especially seeing blood) or pain.
Your doctor might do a tilt table test, which is where you’re strapped to a table that’s slightly upturned and your heart and blood pressure are measured. This will trigger a fainting response in many people with vasovagal syncope.
When you are having a fainting episode, your doctor will give you medicines to help slow your heart rate and keep it steady so that you can get back to your normal breathing and heart rate. These medicines are usually called calcium channel blockers, such as Florinef or Midodrine.
The doctors will also take notes about your symptoms. They’ll tell you what they find, and if you have any warning signs before the fainting episode, they’ll mention them as well.
Most people who have this type of fainting will not need treatment, but your doctor might suggest a special diet and a medication that reduces your risk of having another episode. Some children and young adults need a medication that increases their potassium levels in the blood, which helps to stabilize the heart’s rhythm and slows down your heart rate.
Some people will need other tests. These can be used to determine the underlying cause of their syncope, like an ECG or 24-hour Holter monitoring. These are not invasive procedures and don’t require hospital admission.