Rheumatoid arthritis (RA) is an autoimmune condition that mainly affects a person’s joints. However, RA can also cause symptoms that affect the gastrointestinal (GI) system, such as nausea, indigestion, and abdominal pain.

The GI system contains many different organs, including the:

This article discusses the effect of RA on the GI system, and the resulting symptoms. It also provides information on the relationship between GI problems and RA medication, as well as treatment options and prevention methods.

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There are many important connections between the GI system and RA. Some scientists believe RA could occur due to complex interactions between the gut microbiome, genetics, and environmental factors.

RA is an autoimmune disease. This means that it develops when a person’s immune system, whose role is to protect the body against disease, attacks healthy cells instead.

The primary symptom of RA is inflammation of the joints. However, RA can affect almost every organ in the body, including the GI system.

According to the Arthritis Foundation (AF), people with RA are approximately 70% more likely to develop GI problems than those without the condition.

This can occur for a variety of reasons, such as:

Some RA medications can produce GI side effects. The AF notes that medications for RA are the most likely cause of GI symptoms.

A 2018 article lists some common RA medications together with their side effects.


NSAIDs can help relieve pain and reduce inflammation. However, prolonged use can lead to the following:

Effect on GI systemResulting symptoms
nausea and vomiting
loss of appetite
• weight loss
abdominal pain
GI bleeding• abdominal cramps
• tarry or black stool
vomit resembling coffee grounds
blood in stool
• red blood in vomit
colitis• diarrhea
• abdominal pain
• frequent urge to empty the bowels
hepatotoxicity• pain in the upper right abdomen
• loss of appetite
• nausea
• vomiting
• tea-colored urine


DMARDs are a group of medications that help slow the progression of RA. However, they can cause the following GI symptoms:

DrugResulting symptoms
methotrexatestomatitis, which is inflammation of the mouth
• nausea
• abdominal pain
• hepatotoxicity
• diarrhea
leflunomide• nausea
• abdominal pain
• diarrhea
• hepatotoxicity
hydroxychloroquine• abdominal pain
• nausea
sulfasalazine• abdominal pain
• nausea
• vomiting
• diarrhea
• hepatotoxicity
azathioprine• anorexia
• nausea
• vomiting
• hepatotoxicity
Janus kinase inhibitors• abdominal pain
• nausea
• vomiting
• diarrhea
GI perforations

DMARDs can also lower the body’s ability to fight off infections. As a result, bacterial infections, such as bacterial colitis and diverticulitis, can occur.

Bacterial infectious colitis can cause abdominal pain and diarrhea. Diverticulitis can lead to diarrhea, constipation, and abdominal pain on the lower left side.


Corticosteroids can help alleviate inflammation. However, they can also weaken the immune system. This increases the likelihood of developing fungal infections, such as oral thrush.

Among symptoms of oral thrush are:

  • cracks at the corners of the mouth
  • an unpleasant taste in the mouth
  • mouth pain, such as sore gums
  • difficulty drinking and eating
  • loss of the ability to taste things

Corticosteroids can also result in ulcerations and visceral perforation, which is when a hole forms through the stomach, large bowel, or small intestine.

Visceral perforation can cause severe stomach pain, nausea, vomiting, chills, and fever.

Tumor necrosis factor inhibitors

Tumor necrosis factor (TNF) inhibitors aid in reducing inflammation. However, they can produce the following GI symptoms:

  • abdominal pain
  • nausea
  • vomiting
  • diarrhea
  • oral ulcers
  • gastritis, which is inflammation of the stomach lining
  • hepatotoxicity

They can also cause bowel obstructions, which can result in:

Bowel perforations can also occur, which can lead to the following:

  • severe abdominal pain
  • fever
  • chills
  • abdominal swelling and bloating
  • nausea
  • vomiting

According to research, RA can affect the GI system in a number of ways.

Below, we outline these conditions along with their symptoms.


In rare cases, individuals with RA will develop RV. This can affect approximately 5% of those with RA.

RV is the inflammation and narrowing of the blood vessels. Although it typically affects the nerves, skin, fingers, and toes, it can also cause inflammation in the GI tract.

Among GI symptoms of RV are:

  • weight loss
  • loss of appetite
  • abdominal pain
  • diarrhea
  • stomach ulcerations
  • ulcers in the esophagus
  • bowel perforation
  • bloody stools

Other symptoms include:

Felty’s syndrome

In rare cases of RA, people may develop Felty’s syndrome. This condition causes various abnormalities of the liver, including:

  • an enlarged liver
  • varices, which are swollen or enlarged veins
  • fluid buildup in the abdomen

People with RA are more likely to develop certain autoimmune conditions, which can cause GI problems.

These conditions include:

Autoimmune hepatitis

Symptoms of autoimmune hepatitis vary but can include:


Symptoms of IBD include:

  • abdominal pain, cramps, and swelling
  • bloody and recurring diarrhea
  • weight loss

Celiac disease

Celiac disease can manifest in various ways, including:

Secondary Sjögren’s disease

Secondary Sjögren’s disease occurs alongside rheumatic conditions, such as RA.

Up to 31% of people with RA may develop secondary Sjögren’s disease. In the case of people with RA, this condition will affect the mouth.

It can cause dry mouth, which could impede chewing or swallowing. It also causes enlarged parotid glands, which are the two salivary glands just in front of the ears that produce saliva to help with chewing and digestion.

AA amyloidosis

AA amyloidosis is another rare complication of RA, occurring in 0.6–1.1% of people with this type of arthritis.

It can affect the esophagus, stomach, intestines, liver, or gallbladder in people with RA.

Symptoms include:

Medical treatment for GI complications of RA depends on the cause of the complications. For example, in order to treat a person’s amyloidosis, doctors must treat its underlying cause, which in this case is RA.

However, some RA treatments can cause GI symptoms.

To help relieve mouth sores, a person can try a saltwater rinse or use a mouthwash that contains lidocaine.

Additionally, a healthcare professional may be able to prescribe anti-nausea medication to help reduce feelings of nausea.

A person can discuss ways to reduce GI symptoms with a rheumatologist.

Certain GI symptoms may be harder to treat than others. For instance, because RV is a rare complication of RA, scientists have not collected much quality evidence about effective treatments.

A person with RA may also be able to relieve certain GI symptoms, such as nausea and dry mouth, without using medications. A doctor can advise them about safe home remedies to address such symptoms.

Moreover, physiological health conditions can negatively impact a person’s psychological well-being. Some people with RA might therefore benefit from attending to their mental well-being by:

RA and the various GI symptoms it can cause arise from a complicated mix of biological and environmental factors.

A person may not be able to prevent some GI symptoms. However, their diet can help improve some RA symptoms.

Learn more about what foods to eat and avoid for RA here.

Individuals can also try taking folic acid to prevent some side effects that occur as a result of RA medication.

Some healthcare professionals may recommend taking 1 milligram (mg) of folic acid per day. Others may suggest taking 5 mg of folic acid per week in a single dose.

Learn more about methotrexate and folic acid for RA here.

Anyone with GI symptoms should promptly seek guidance from a doctor.

The same is true for other symptoms of RA, such as:

It is also important for people taking RA medications to look out for any GI side effects.

RA is a common condition that affects the joints. However, there is a strong connection between RA and the GI system. That is why RA can also lead to GI problems.

Although these symptoms can be difficult to manage, treatment options are available. A person should seek guidance from a healthcare professional to help them find the most suitable treatment.