People with irritable bowel syndrome (IBS) have an increased risk of headache disorders, especially migraine. Links between the two conditions include hormones and other factors involved in the gut-brain axis.

If you often deal with headaches, especially migraine episodes, then you already know they can mess up your stomach — nausea, vomiting, diarrhea, and loss of appetite are all common side effects.

But is the opposite true? For instance, if you have irritable bowel syndrome (IBS), can it cause headaches? Some researchers are starting to think yes, thanks in large part to the gut-brain connection.

While IBS doesn’t cause headaches or migraine, there’s a correlation between the two conditions that can’t be ignored. Here’s what we know so far about the connection between these two common conditions, from how to figure out what you’re dealing with to how you can treat both at the same time.

There is a connection between IBS and headaches. People with IBS have an increased risk of developing a primary headache disorder like tension-type headache or migraine.

In a 2020 study of 2,885 individuals, people with IBS had a 44% chance of co-existing headaches, while people without IBS only had a 23% chance of headaches.

Another small study, published in 2016, found that about 22% of people with IBS had tension-type headache, but more than 35% had migraine. This suggests that migraine is more common among people with IBS than tension-type headache.

For this reason, much of the research about IBS and headaches focuses on migraine.

One of the largest studies ever done on migraine and IBS, published in 2006, found that people with IBS are more than 1.5 times more likely to have migraine than those without IBS.

People with migraine also have an increased risk of developing IBS than people without migraine. The small study also found that participants with migraine were twice as likely to have IBS as people without migraine.

In general, tension headaches:

  • are related to stress and muscle tension
  • usually cause mild to moderate pain on all sides of the head
  • can cause neck pain
  • usually don’t cause nausea or vomiting, or sensitivity to lights, sounds, or smells

Migraine is a neurological condition with its own set of symptoms:

  • often cause throbbing or pulsing pain only on one side of the head
  • are often severe and get worse with activity
  • can cause nausea and vomiting, as well as sensitivity to lights, sounds, and smells
  • may or may not be preceded by aura
  • can last several hours to several days

Doctors and researchers aren’t entirely sure why there’s a strong link between IBS and migraine, but there are some things that can increase your likelihood of developing either of the conditions (and, therefore, could result in you ending up with both).

Genetics

It appears that migraine, tension-type headache, and IBS may all share some genetic components.

One small 2016 study found several genetic similarities, which may suggest similar physiological origins for these conditions. The study found that participants with both IBS and a primary headache disorder had at least one gene that differed from the genes of the healthy control group.

Pain sensitivity

IBS and migraine are sometimes categorized as chronic pain conditions that could involve heightened pain sensitivity in the gut and brain. This is one reason why experts think some people develop these conditions while others don’t.

The authors of a 2020 research study note that hypersensitivity of the enteric nervous system (which regulates your GI tract) has been observed in patients with IBS, while hypersensitivity of pain pathways in the brain is often cited as a causal factor in migraine.

This has led some researchers to suggest that people with IBS and migraine are more sensitive to stimuli in general. This sensitivity might affect several body systems and cause multiple diagnoses related to pain response.

Hormones

IBS and migraine are both more common in women, so there’s good reason to think that hormones like estrogen may be partly to blame for causing gut and brain disorders.

Unfortunately, the effects of hormones such as estrogen and progesterone on IBS aren’t well-studied. But, anecdotally, many women with IBS report worsening symptoms around the time of menstruation.

Migraine has long been linked to fluctuating hormones; in fact, there’s a type of migraine called menstrual migraine, which causes symptoms right before or during menstrual periods. In particular, changing estrogen levels are usually associated with menstrual migraine.

Serotonin

Some researchers believe the body’s gut-brain connection may be responsible for IBS and migraine. They’ve specifically considered low serotonin levels in the gut as a possible factor.

Past research has found low serotonin levels in people with migraine and people with IBS, and this may be part of the reason why selective serotonin reuptake inhibitors (SSRIs) are sometimes used for the treatment of IBS.

Since migraine can cause digestive symptoms, it can be tough to figure out whether your nausea and diarrhea are migraine side effects or symptoms of IBS.

GI-related symptoms of migraine include:

  • nausea
  • vomiting
  • diarrhea
  • loss of appetite

GI-related symptoms of IBS include:

  • abdominal pain and cramping
  • diarrhea
  • constipation
  • bloating and gas
  • blood or mucus in stool

Migraine in children

While many kids with migraine have typical symptoms, some experience abdominal migraine, a form of migraine that’s essentially a migraine episode without any headache or head pain.

Abdominal migraine causes nausea, vomiting, stomach pain, diarrhea, and loss of appetite, and usually only affects kids under the age of 10. Some of these kids outgrow abdominal migraine while others go on to have more typical migraine symptoms as they get older.

In the younger years, it can be difficult to distinguish IBS from abdominal migraine in kids, but a doctor can help by taking a family and medical history.

If you’ve been diagnosed with migraine or IBS, you’ve probably been told to keep a food diary, which is a daily account of everything you eat and drink. That’s because certain foods can trigger both IBS and migraine symptoms, and figuring out what foods to avoid with IBS and migraine can reduce the number of attacks you experience.

Keeping a food diary is relatively self-explanatory: write down whatever you eat and drink, along with the quantities, from the time you wake up until the time you go to bed. Make sure to date each entry. Also make sure to note any condition-specific symptoms you experience, as well as the time or duration of those symptoms.

Treating migraine and IBS might involve coordinating care between different healthcare providers, as some medications may be used to treat both conditions, but others can interact in negative ways. Medications that can help with migraine and IBS may include the following:

  1. Antidepressants: Some tricyclic antidepressants, like nortriptyline, are used in the treatment of migraine, and some SSRIs (as well as some tricyclic antidepressants) may be used to treat IBS symptoms.
  2. Anti-nausea drugs: Nausea and vomiting are symptoms of migraine and IBS, so antiemetic drugs may be used in both cases. Zofran may also reduce diarrhea in people with IBS.

On the other hand, some drugs commonly prescribed for migraine can exacerbate GI issues like diarrhea and constipation, especially if you have IBS. Triptans such as Imitrex or Frova and CGRP antagonists, like Emgality, have been shown to cause constipation.

Medications used to reduce diarrhea or constipation, improve gut health, and reduce intestinal muscle spasms aren’t likely to interfere with migraine treatments.

If your IBS or migraine symptoms affect your quality of life, it’s time to make an appointment with a healthcare professional. Your symptoms shouldn’t cause you to miss work or school, disrupt your normal sleep schedule, or interfere with your relationships.

As for what kind of doctor to see, it may depend on your medical history. But it’s always good to start with a general practitioner. They may refer you to a gastroenterologist or a neurologist.

Although migraine episodes can cause some GI disturbances like nausea and vomiting, people with migraine also have a higher incidence of IBS than other people. While IBS doesn’t cause migraine — and migraine doesn’t cause IBS — different factors can result in people having both conditions.

If you think you have migraine and IBS, it’s important to have a team of healthcare professionals working with one another and with you to manage your symptoms and collaborate on treatments.