Conditions That Cause Erythematous Mucosa

"Erythematous mucosa" is a term to describe the inflammation and redness of the inner lining of the digestive tract. Erythematous mucosa is associated with conditions such as gastritis (inflammation of the stomach lining), colitis (inflammation of the lining of the colon, or large intestine), and proctitis (inflammation of the rectum).

This article will discuss the various underlying conditions that may cause inflammation within the gastrointestinal tract, their causes, symptoms, treatment options, and more.

Woman holding her stomach in pain.


Causes of Erythematous Mucosa

Various conditions are characterized by erythematous mucosa, including gastritis, Crohn’s disease, and ulcerative colitis. Each condition has specific signs that may indicate inflammation or injury. 


There are various causes of gastritis leading to inflammation in the stomach, including:


Often, the specific cause of colon inflammation or colitis is unknown, but may include the following:

  • Infections related to a parasite or virus
  • Bacteria that cause food poisoning 
  • Impaired blood flow, called ischemic colitis 
  • Radiation in the colon (causing radiation colitis) 
  • A condition in newborns called necrotizing enterocolitis, which leads to tissue death in the colon (can impact premature or sick babies, and the exact cause is unknown) 
  • Clostridioides difficile,(C. diff) a bacterium that causes colitis 

Crohn’s disease and ulcerative colitis are two of the most common types of inflammatory bowel disease. They are:

  • Crohn’s disease affects parts of the digestive tract and often causes inflammation at the end of the small intestine and the beginning of the large intestine. Crohn’s disease is an autoimmune disease, meaning the immune system attacks healthy tissue. The exact cause is unknown.
  • Ulcerative colitis affects the lining of the large intestine and the rectum. The cause is unknown, but individuals with ulcerative colitis typically also have immune system issues. Stress and certain foods can aggravate and trigger symptoms, but it is not the cause of this condition.


Proctitis refers to inflammation of the rectum. There are many causes, including:

  • Inflammatory bowel diseases, such as Crohn’s disease and ulcerative colitis 
  • Autoimmune diseases 
  • Sexually transmitted infections (STIs), including gonorrhea, herpes, and chlamydia
  • Bacterial infections
  • Certain medications, like those used for radiotherapy in the prostate or pelvis

Condition-Specific Signs of Erythematous Mucosa

Depending on the underlying condition causing erythematous mucosa, symptoms will vary.


Many individuals with gastritis don’t have symptoms. Those with symptoms may experience the following:

  • Loss of appetite
  • Nausea and vomiting 
  • Pain in the upper part of the abdomen 
  • Bleeding that can cause black stools 
  • Bleeding that can cause vomiting blood or coffee ground-like substance


Crohn’s disease and ulcerative colitis share several symptoms. 

The main symptoms of Crohn’s disease are:

  • Abdominal cramps and pain 
  • Fever
  • Fatigue 
  • Loss of appetite and weight
  • Feelings of needing to pass stool
  • Watery diarrhea that may have blood 

Other symptoms of Crohn’s disease are:

  • Joint pain and swelling
  • Ulcers in the mouth
  • Red bumps or nodules under the skin that may develop into ulcers 
  • Constipation 
  • Sores or swelling in the eyes
  • Draining of pus, mucus, or stool from the rectum or anus due to fistula (an abnormal connection between organs and/or skin)
  • Rectal bleeding and blood in the stool
  • Swelling of the gums 

Similarly, ulcerative colitis may also present as:

  • Abdominal cramps and pain 
  • Fever 
  • Weight loss
  • Feelings of needing to pass stool 
  • Diarrhea 
  • Blood and sometimes pus in the stool

Additional common symptoms of ulcerative colitis include:

  • Sounds of gurgling or splashing in the intestines 
  • Slow growth in children

Other less common symptoms include:

  • Joint pain and swelling
  • Sores or ulcers in the mouth 
  • Red bumps or nodules under the skin that may develop into ulcers 
  • Nausea and vomiting


Since inflammation in the colon due to Crohn’s disease or ulcerative colitis can be the cause of proctitis, there is an overlap in symptoms. These include:


Treatment will vary based on whether the erythematous mucosa is in the stomach, colon, or rectum. The underlying cause of the inflammation will also influence treatment. 


Treatment for gastritis includes:

  • Stopping medications that may worsen the condition, like the NSAIDs aspirin, ibuprofen, and naproxen 
  • Taking over-the-counter (OTC) drugs that decrease stomach acid, such as antacids (Tums), H2 antagonists (Pepcid), and proton pump inhibitors (Prilosec)
  • Antibiotics if the cause of gastritis is the bacteria H. pylori 
  • Managing diet to avoid triggering foods


The goal of treatment with inflammatory bowel diseases is to control symptoms, prevent repeated attacks, and help the colon heal. 

Crohn’s disease can be managed through diet, stress management, supplementation as needed, medication, or surgery:

Dietary recommendations include:

  • Eating small, frequent meals 
  • Drinking enough water
  • Avoiding high-fiber foods
  • Avoiding fatty, greasy, fried food and sauces with butter, margarine, or heavy cream 
  • Limiting dairy
  • Avoiding foods that can cause gas, like those in the cabbage family 
  • Avoiding spicy foods

Stress management is recommended as stress may worsen digestive issues.

Supplementation may be indicated if the individual is deficient. Common deficiencies due to inadequate absorption in the small or large intestine include iron, calcium, and vitamin B12.

Medication may help treat the symptoms, including:

Surgery may remove a damaged portion or the entire colon. An ileostomy may remove waste when the colon or rectum is removed or isn’t working properly. 

Dietary recommendations are the same for Crohn’s disease and ulcerative colitis. Individuals with ulcerative colitis should also make an effort to manage their stress. 

Severe ulcerative colitis symptoms may require hospital treatment, corticosteroids, and intravenous (IV) nutrient administration.

The entire colon and rectum may be removed in cases where:

  • Medication doesn’t improve symptoms
  • Changes to the lining of the colon increase risk of cancer
  • The colon ruptures
  • Severe bleeding
  • Toxic megacolon (a severely inflamed colon causes insufficient blood flow)


Inflammation in the rectum usually goes away when the underlying cause is treated. Antibiotics may be used if an infection is the cause of the inflammation. Corticosteroids, mesalamine suppositories, or enemas may help relieve symptoms.

Recurring Symptoms and Possible Complications


The prognosis for inflammation of the stomach is often good, but it depends on the underlying cause of gastritis. Blood loss is a possible complication of gastritis.


Crohn’s disease is incurable and alternates between periods of improvement and flare-ups. A higher risk of cancer in the small bowel or colon is a complication of this condition.

About half of people with ulcerative colitis have mild symptoms. Severe symptoms associated with ulcerative colitis tend to be less responsive to medication. The risk of developing cancers increases with each decade after diagnosis.

Complications include the thickening of the intestinal walls causing severe flare-ups. This thickening can cause:

  • Colon narrowing or blockage 
  • Severe bleeding
  • Severe infection
  • Toxic megacolon
  • Perforation of the colon (tears or holes)
  • Anemia

Ulcerative colitis can also present problems with nutrient absorption, which can contribute to the following:

  • Osteoporosis 
  • Issues with maintaining a healthy weight 
  • Slow growth and development in children 
  • Anemia


Proctitis tends to have a good outcome with treatment. Possible complications include:

  • Anal fistula
  • Anemia
  • Recto-vaginal fistula in women
  • Severe bleeding

Cancer Risk

Cancer risk increases with the state of inflammation in the various areas of the digestive tract. Below are potential risks to be aware of.

  • Inflammation in the stomach increases the risk of gastric cancer.
  • Individuals with Crohn’s disease may be at higher risk of small bowel or colon cancer. Screening for colon cancer, including a colonoscopy, may be recommended for those with Crohn’s disease for more than eight years.
  • The risk for cancer increases each decade after being diagnosed with ulcerative colitis.

A healthcare provider can help monitor your inflammation and recommend screening for cancer if needed.


Erythematous mucosa refers to redness and inflammation in the digestive tract lining, including the stomach, colon, and rectum. Various health conditions can lead to inflammation and redness, including gastritis, Crohn’s disease, ulcerative colitis, and proctitis.

Treatment will vary depending on the condition’s cause and the severity of your symptoms. Medical treatment and monitoring will help manage symptoms and flare-ups. Inflammation of the stomach, small bowel, and colon can increase an individual’s risk of developing cancer, so a healthcare provider may recommend screenings. 

A Word From Verywell

Gastritis, Crohn’s disease, ulcerative colitis, and proctitis symptoms can be uncomfortable and embarrassing. It can be frustrating to deal with digestive discomfort, but managing lifestyle factors like diet and stress can help. Working with a healthcare provider you trust can help you manage symptoms and work towards healing your digestive tract.  

Frequently Asked Questions

  • How do you know if you have stomach inflammation?

    Often an individual with stomach inflammation or gastritis will not experience symptoms. If they do, symptoms may include loss of appetite, nausea, vomiting, pain in the upper part of the abdomen, black stools due to bleeding, or vomiting blood or a substance resembling coffee grounds.

  • Is erythematous the same as erythema?

    The medical terms "erythematous" (adjective) and "erythema" (noun) are used to describe abnormal redness in the mucosa or skin due to injury or inflammation. 

  • Can you treat erythematous naturally?

    It depends on the severity of the symptoms. Most conditions that cause erythematous mucosa require changes to diet and lifestyle. If symptoms are severe or unmanageable, they may require medication or surgery. There may also be natural home remedies that can help alleviate symptoms such as nausea

  • What are the worst and best foods for digestive inflammation?

    Certain foods can help ease or worsen symptoms. Dietary recommendations for digestive inflammation include:

    • Eating small, frequent meals 
    • Drinking enough water throughout the day
    • Avoiding high-fiber foods
    • Avoiding fatty, greasy, fried food and sauces with butter, margarine, or heavy cream 
    • Limiting dairy
    • Avoiding foods that can cause gas, like foods in the cabbage family 
    • Avoiding spicy foods 

    Trigger foods vary by person, so understanding what triggers your symptoms can help ease digestive discomfort. 

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Pennelli G, Grillo F, Galuppini F, et al. Gastritis: update on etiological features and histological practical approach. Pathologica. 2020;112(3):153-165. doi:10.32074/1591-951X-163

  2. MedlinePlus. Colitis.

  3. MedlinePlus. Crohn's disease.

  4. MedlinePlus. Ulcerative colitis.

  5. MedlinePlus. Proctitis.

  6. MedlinePlus. Gastritis.

By Rebecca Valdez, MS, RDN
Rebecca Valdez is a registered dietitian nutritionist and nutrition communications consultant, passionate about food justice, equity, and sustainability.