top of page
  • Dr Andy Raffles

Dizziness & Fainting in Teens

Updated: Sep 3, 2020

Passing out or fainting (also known by the medical term, syncope) is common among young people, especially teenagers. As many as 1 in 4 healthy children and adolescents have fainted at some point.

Although the experience can be frightening, it is usually not caused by anything serious. Most young people recover quickly after fainting, typically in less than one minute.

It is important for parents to learn about common fainting triggers such as dehydration and get prompt treatment when needed. A visit to the GP, Paediatrician or Cardiologist may be necessary, to rule out rare but potentially serious causes of fainting, particularly if there is a family history.

What causes a healthy child to faint?

Most often, fainting happens in otherwise healthy children when there is a temporary drop in the flow of blood to the brain which is usually maintained by blood pressure. A drop in blood pressure leads to reduced blood flow to the brain and this leads to the protective reflex we see as a faint. Usually, the child recovers quickly. This is called simple fainting.

Triggers for simple fainting can include:

  • Not drinking enough fluids, especially during hot weather or in overheated spaces. Dehydration is the most common cause of fainting in children. Not drinking enough fluids also reduces blood volume and lowers blood pressure. A healthy adolescent should drink at least 1.5 litres per day

  • Standing still for a long time in one place. This can cause the blood to pool in the legs because of gravity or standing up quickly

  • Overheating, especially in overcrowded environments

  • Strong emotions in response to pain, blood, or something shocking or scary. This can cause the part of the brain that controls blood pressure, breathing rate, and heart rate to suddenly switch gears and get out of sync

  • Hyperventilating or breathing too fast. This can happen due to anxiety or fear because it causes rapid changes in our blood supply to the brain

  • Breath-holding spells. These are common in young children during temper tantrums or when they are in pain. Breath-holding spells generally are not serious, and most children outgrow them by 6 years of age

  • Certain movements, such as coughing, swallowing, weightlifting, going to the bathroom, or even hair-grooming may stretch or press on sensitive nerve endings. This trigger is rare and usually affects teens; with the vast majority outgrowing it

  • The choking game: beware of dangerous internet challenges! - the “choking game," the "fainting game," "pass out," and "blackout", names of a few of the dangerous internet challenges on social media where kids try to faint on purpose. The "challenge" involves cutting off blood and oxygen to the brain by wrapping a belt or a similar object around the neck to experience a "high" when letting go. Signs your child might be trying it, include bloodshot eyes and frequent headaches. Talk with your kids about how internet challenges that may seem harmless and funny, can easily land them in the hospital

What are some warning signs and symptoms before fainting?

About 5 to 10 seconds before fainting, there are several warning signs including:

  • Dizziness or light headiness

  • Nausea

  • A surge of warmth and sweating, or sudden cold feeling

  • Blurry or spotty vision

  • "Ringing" in the ears

  • Pale or ashy appearance

  • Faster heart rate (called tachycardia)

Informing the teachers if you child has fainted before may be helpful, as they will be able to look out for signs whilst at school and put additional measures in place to help avoid happening again, such as, encourage your child to stand at the end of a row, or provide a chair when in school assemblies.

What to do when a child faints:

  • If possible, try to catch and ease the child to the floor

  • Have the child raise both legs for 10 minutes while lying down

  • If the child has food in their mouth, lay on their side with face turned towards the floor so as not to choke on the food

Call 999 or go to the nearest emergency department if the child:

  • Is not waking up after a short amount of time i.e. within 10 minutes

  • Has injuries from the fall and is bleeding a lot

  • Fainted suddenly after taking medicine, being stung by an insect, or eating something that they may be allergic to

  • Was exercising when they fainted

  • Is having trouble breathing, talking, or moving

Some ideas on how to avoid faints:

  • Stay hydrated and eat well. Make sure your child drinks plenty of water or other healthy beverages each day. Limit caffeine and avoid skipping meals

  • Monitor blood pressure. If your child's blood pressure is low or normal, your Paediatrician may suggest a change in his or her diet

  • Flex muscles in the legs, shift positions, and bend at the waist occasionally when standing for a long time to help circulation and blood flow to the brain

  • Take breaks from the heat. Avoid standing for long periods in warm environments, such as practice fields in the sun or crowded places. Limit time in hot showers, saunas, hot tubs, and Jacuzzi

  • Help your child learn to recognise the early signs of fainting. When symptoms start, remind to put their head between their legs or lay down

Can fainting be a sign of a more serious medical condition?

In some cases, fainting can be a sign of an underlying health problem or condition, such as:

  • Iron-deficiency. Anaemia, when there's insufficient iron in the blood to deliver enough oxygen to brain, can cause of fainting in rapidly growing teen, especially girls who get heavy periods

  • Internal bleeding. A blow to the head (such as a concussion) or belly

  • Diabetes. Sudden drops in blood sugar can cause fainting. The brain needs sugar for energy. Diabetes also can cause increased urination that leads to dehydration. If a child with diabetes faints, it is considered a diabetic emergency

  • Eating disorders. Anorexia and bulimia can cause fainting from dehydration, low blood sugar, and changes in blood pressure or circulation caused by starvation, vomiting, or over exercising

  • Heart issues. Irregular heartbeats (cardiac arrhythmia) or structural problems (heart or valve) can cause fainting. Fainting that happens during exercise always needs medical follow-up

  • Migraines. Fainting is a symptom of certain types of migraine headaches

  • Alcohol and drug use. Alcohol makes blood vessels dilate or widen which can cause the blood pressure to drop. Some illegal drugs, like methamphetamine, affect heart function and can lead to fainting

  • Pregnancy. Though unlikely to be the case, changes to the circulatory system in pregnancy can affect blood pressure and increase the body's need for fluids

  • Postural Orthostatic Tachycardia Syndrome (POTS). This condition affects an estimated 1 in 100 teens who get a rapid heartbeat and light headiness or fainting when standing, especially after lying down. Episodes often start after viral illness, trauma, or major surgery

  • Addison's Disease/adrenal insufficiency. Children with this condition do not produce enough hormones, such as cortisol, that help control the response to stress, blood pressure, and blood sugar levels


Most children and teens who faint recover quickly and without any lasting harm. Knowing how to help prevent fainting spells, like getting plenty of fluids, can help avoid the scary experience of passing out. Any time your child does faint, be sure to tell your GP or Paediatrician.

23,185 views0 comments
bottom of page