Nausea & Vomiting

There are many causes of nausea and vomiting while running, while some are concerning most are not dangerous. However, it remains difficult to consistently treat. Vomiting doesn’t necessarily mean you need to end your race. You may be able to “Puke and Rally”!

Determining a cause

This may be difficult but the main questions to answer: Is this dangerous or concerning? When you are assessing potential causes keep in mind there may be multiple things contributing, such as heat and over hydration.

What does it look like?
Does the emesis (vomit) look like what you have been eating or is there blood or dark, coffee ground looking material in it?

– If it looks like regular vomit (undigested/partially digested food, liquid) this is less concerning and proceed to evaluate other symptoms

– If there is blood in the vomit you should stop. Small streaks may indicate a small tear in the lining of GI tract or irritation. More obvious blood or clots should seek expeditious medical evaluation. Coffee ground looking material can represent digested blood if you have not been eating foods that may have this appearance.  Certain medications such as NSAIDS will increase your risk for GI bleeding.

Recent bowel movements
If you have had a recent bowel movement was there blood in it or black, tarry looking stool? If yes this suggests gastrointestinal bleeding as well and you should seek medical attention. NOTE: some medications such as Pepto can turn your stool black and some foods, like beets, can give the appearance of blood.

Is there just vomiting or are there other symptoms?
No other symptoms—when you exercise, blood flow preferentially goes to the muscles and not the gut.  Consider slowing down or resting to rebalance. Consider the foods/drink you have taken. Is there a new food/drink that your body is reacting poorly to? Certain foods such as those high in fiber or fat may cause more GI distress. Have you eaten too much? Have you eaten too little? Both can lead to nausea.

Vomiting and headache?—Consider your hydration status—both overhydration/hyponatremia and dehydration can cause vomiting.

What is your hydration status?
Have you been “drinking to thirst” or drinking substantially more than this? If you have been drinking too much and are vomiting you may be overhydrated/hyponatremic. NOTE: you can be overhydrated even if you are using electrolyte drink and not just plain water. Look for other signs such as swelling in the hands or legs or weight gain (these are not always present). If you have been drinking too much and are vomiting without other symptoms such as confusion, you should stop and rest. While stopped don’t drink more water but you can drink a concentrated sodium solution such as 4 bullion cubes in 125mL water (you may want to flavor this as well). You are usually okay to continue racing if symptoms resolve and you keep a close eye on your hydration status.

Are you dehydrated? Have you urinated recently and how did it look?  If the answer is no or the urine looked very dark and you have not been drinking much you are likely dehydrated.  Consider slowing or resting and increasing hydration. Does your urine look brown like soda or tea? If so you may have rhabdomyolysis and you should hydrate and seek medical attention.


Did you fall?
Have you fallen recently and potentially hit your head? If yes then you should stop and seek medical attention.

Your environment
What is the environment? Are you are at altitude or in warm weather? If yes proceed to race conditions segment.

Vomiting and dizziness?

Similar to headache

Chest pain
Do you have any chest pain with the vomiting and dizziness? If yes seek medical attention

Heart rate
Is your heart rate fast even when resting? If it is fast and irregular at rest seek medical attention. If it is fast and regular (steady) consider hydration status, conditions, etc. If your HR is not improving even after resting for 5-10 minutes you should stop and seek medical attention.

Racing conditions
Consider the race conditions

Vomiting and confusion
Seek medical attention

Vomiting and abdominal pain
Is the pain a crampy pain that comes with vomiting? If yes, then rest and treat the nausea.

Is the pain sharper and constant and does it hurt to push on? If yes, a trial of time is reasonable but if it does not improve you should stop and seek medical attention.

Vomiting and diarrhea
Without other symptoms, you can treat both and continue. You may want to pack extra shorts.

Race Conditions

High altitude is typically considered to begin at 8,000 feet although you may feel some effects at lower elevations. Most of the dangerous complications of altitude occur at over 10-12,000 feet. If you are racing at altitude, regardless of acclimatization you are at risk. You are at increased risk without acclimatization.

Isolated vomiting or vomiting with fatigue and mild headache
This can suggest acute mountain sickness which is not dangerous but uncomfortable. Usually okay to continue if you slow effort and monitor symptoms closely. Often the increased stress of altitude can increase nausea so consider timing your fueling to descents or lower sections of the course.

Vomiting with confusion or severe headache or ataxia (unsteady walking)
Descend immediately and seek medical attention. You may be at risk for severe complications of altitude such as High Altitude Cerebral Edema. Dexamethasone (a prescription steroid) is part of treatment.  Of note it is on the WADA banned list so should not be taken as preventative treatment in a sanctioned race.

While cold temperature can affect the GI tract, the more common concern is with hotter temperatures.

Hot conditions with isolated vomiting or vomiting and fatigue and mild headache, consider slowing and using passive cooling techniques such as ice bandanas or sleeves, cooing in water sources or similar.

Hot conditions with vomiting and confusion, ataxia (unsteady walking), or seizures. Stop and cool immediately while seeking medical care. Cold water immersion such as in a creek is ideal. Other methods such as spraying with water and fanning, ice packs, and getting out of direct sunlight are also helpful. This is a dangerous situation that could be heat stroke and the sooner you can cool the runner the better. LINK


Specific instances are addressed in the respective sections and the following methods apply in most cases.

Decrease your effort
Slow down or rest.

Take small sips of fluid and small amounts of fuel (gel, foods, etc.)

Listen to your body
Have you eaten 100 gels and no salty foods? Consider some salt. Have you been chugging broth all day? Consider plain water and something sweet. Do you feel like you are craving chips or a perogi? Try them.

Alcohol wipes
Studies demonstrate effectiveness similar to medications in hospital patients by smelling an alcohol wipe. Try it!

Ginger-based products
Ginger-based products, chews, lozenges, etc.

Over the counter medications
Medications specifically designed for nausea such as Pepto or Tums may help. 

Prescription medications
Prescription medications such as ondansetron can be helpful but must be prescribed or given by a doctor.


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