Headache and Diarrhea: 5 Possible Causes

Diarrhea itself is a gastrointestinal disorder that can occur due to viral or bacterial causes but some diseases have headache and diarrhea as their associated symptoms. Some of such conditions are given below:

  1. Migraine
  2. Norovirus
  3. Coronavirus
  4. Stomach flu
  5. Alcohol-induced headache

1- Migraine

Most of the population around the world suffers from migraines. Migraine is a unilateral headache that is throbbing in character and occurs due to overreacted nerve cells. Nausea and vomiting are common migraine symptoms but the unclear association seen here is with diarrhea. People who experience regular GI symptoms such as constipation are more likely to experience migraines. One possible association between headache and diarrhea could be the increased permeability of the gut and the inflammation that occurs.


  • The GI issues would require dietary changes and additional prophylactics for those who face these complications very often.
  • Triptans, anti-inflammatories, and Excedrin are helpful for the migraine.

2- Norovirus

Norovirus illness involves an inflamed stomach or intestine and is better known as acute gastroenteritis. Symptoms usually develop within a couple of days of exposure to the virus and might vanish in another 3 to 4 days. Norovirus can cause severe symptoms such as several episodes of vomit or diarrhea that can develop into dehydration.


  • Dizziness
  • Headache
  • Diarrhea
  • Nausea and excessive vomiting
  • Decreased frequency of urination after the development of dehydration


  • Being a viral disease it is self-limiting and goes away within 7 days of exposure. However, symptomatic treatment is helpful.
  • To combat dehydration, oral rehydration serum and intravenous fluids are given.

3- Coronavirus

The notorious coronavirus has a number of symptoms that vary from neurological to gastrointestinal, headache and diarrhea are two such symptoms that are seen in a number of individuals around the globe.


  • Fever
  • Headache
  • Diarrhea
  • Anosmia
  • Hives
  • Lethargy
  • Flu-like symptoms
  • Muscle pain


There is no treatment yet discovered, however symptomatic treatment according to the severity and intensity of symptoms has proven to be very helpful.

4- Stomach flu

Viral gastroenteritis, also known as stomach flu is characterized by rice water diarrhea, cramping in the abdomen, nausea associated with vomiting, and occasionally a headache.
The illness itself is not something to worry about, many of the patients recover without developing any complications.


  • Headache
  • Diarrhea
  • Nausea and vomiting
  • Abdominal pain
  • Fever


  • There is no proper treatment but in case of dehydration caused by excessive diarrhea and vomiting, IV and oral fluids are given.
  • Analgesics can help with headache.

5- Alcohol-induced Headache

Drinking excessive alcohol-containing beverages is often associated with headache and diarrhea that occur along with the hangover.
Ethanol, a chemical present in alcohol-containing beverages is a natural diuretic that causes dehydration.


  • Headache
  • Diarrhea
  • Loss of coordination
  • Blurred vision
  • Photophobia and phonophobia
  • Loss of appetite but increased thirst


  • Anti-inflammatory medications for the headache.
  • Vitamin B6 to hasten the process of removing alcohol from the body.
  • Plenty of water for dehydration

Complications that can arise due to diarrhea

If diarrhea persists for a long time, it can lead to the development of some complications, that is;

  • Severe dehydration
  • Unconsciousness
  • A weak immune system in children

When to consult a doctor?

If the diarrhea lasts more than two days, you are very likely to have become dehydrated. Consult a doctor for your symptoms as soon as possible and start with ORS.


Should I let headache and diarrhea run their course?

No, diarrhea is fought off by your immune system and prolonged condition can make your immune system weak and more prone to developing other super-imposed infections. The headache should be treated with respect to its cause, in case of its association with diarrhea, it will go away with diarrhea and doesn’t need a separate treatment.

What are the first signs of diarrhea?

  • Loose, watery stools
  • Abdominal cramps
  • Fever
  • Bloating
  • Nausea
  • Mucus or blood in the stool

When should I be worried about diarrhea?

As soon as you first experience any symptoms of diarrhea, begin with a rehydration treatment and consult a doctor if your diarrhea persists after two days of onset or if you find mucus or blood in your stool.

How are headache and diarrhea associated with each other?

Increased permeability of the gut and the inflammation that occurs due to diarrhea can cause headaches.

Last medically reviewed on September 9, 2022.