When to Go to the ER for Diverticulitis

Severe diverticulitis symptoms, including sudden, intense, and continuing lower-abdominal or low-back pain, ongoing fever, excessive nausea and vomiting, persistent diarrhea, and blood in your stools, indicate you might need to go to the hospital. Severe diverticulitis may lead to complications that require immediate medical attention.

This article reviews severe symptoms of diverticulitis, possible associated complications, how to know when you need to go to the hospital, and what to expect for diagnosis, treatment, and recovery.

An illustration with information about when to go to the hospital for diverticulitis

Illustration by Mira Norian for Verywell Health

What Is a Severe Attack of Diverticulitis?

A diverticulum is a small pouch, or sac, that forms and pushes outward through weak spots along the wall of the colon (large intestine). Having diverticula (the plural for diverticulum) in your colon is called diverticulosis.

The condition of having inflamed or infected diverticula is called diverticulitis. Diverticulosis and diverticulitis are both known as diverticular disease.

A severe diverticulitis attack usually comes on suddenly.  However, sometimes symptoms may start mild and increase in severity over several days. The intensity of the pain may vary over time.

Diverticulitis Symptoms

Symptoms of diverticulitis include abdominal pain, fever and chills, nausea, vomiting, and constipation or diarrhea. It is important to seek medical attention if you have any of these symptoms. If left untreated, severe diverticulitis can progress into widespread infection.

Abdominal Pain 

Abdominal pain is one of the most common symptoms of diverticulitis. It is most often felt in the lower left side of your abdomen. Pain may also be felt on the right side or in the middle of the lower abdomen.

Abdominal pain and tenderness in a severe diverticulitis attack tend to be persistent and continuous for several days. You might also experience bloating (swelling or feeling of fullness) in the abdomen.


A diverticulitis flare-up may bring on a fever of 100.4 degrees F or higher. Fever may be accompanied by chills.

Nausea and Vomiting

Nausea may lead to decreased appetite during severe diverticulitis. In some cases, you might also experience vomiting. 

Constipation or Diarrhea

A change in bowel habits often occurs during a diverticulitis flare-up. Constipation is more common in someone with diverticulitis. However, sometimes you may experience loose stools and diarrhea. In severe cases, stool may have mucus or blood in it.

Can You Tell If Your Diverticulum Has Burst?

If your diverticulum has perforated (burst), it may cause an increase in the severity of your symptoms, as well as rapid heart rate, dizziness, light-headedness, or weakness. 

A perforated diverticulum may allow bacteria from the bowel to leak into the abdominal cavity. This can lead to peritonitis—an infection of the tissue that lines the abdominal cavity and organs in the abdomen.

A burst diverticulum is a medical emergency and should be treated right away.

When to Go to the Hospital With Diverticulitis

If you are experiencing any symptoms of diverticulitis that are not going away, you should go to the hospital for medical attention. These symptoms include:

  • Sudden and severe lower belly or back pain that doesn’t go away
  • Fever over 100.4 degrees that doesn’t go away
  • Excessive vomiting and nausea
  • Loss of appetite
  • Blood in your stools
  • Persistent diarrhea

Complications of Diverticulitis

Diverticulitis may lead to complications, such as:

Testing to Diagnose Diverticulitis

To diagnose diverticular disease, a healthcare provider will first review your medical history. They will also perform a physical exam. The physical exam may involve feeling your abdomen, using a stethoscope to listen for sounds in your abdomen, and checking your blood pressure, heart rate, and temperature.

You can also expect several tests to be ordered to help rule out other conditions and make an accurate diagnosis. These may include:

Conditions That Mimic Diverticulitis

Several conditions must be ruled out before a diagnosis of diverticulitis is made. This is because they often present with similar symptoms. 

These include:

ER Treatment for Severe Diverticulitis

Severe diverticulitis generally warrants treatment in the hospital. This is especially true if you have developed any complications or have a high risk for complications.

Treatments for diverticulitis may include:

  • Antibiotics: These will fight a bacterial infection.
  • A clear liquid diet: This is recommended for a short time to rest your bowels.
  • Pain medication: You might be prescribed antispasmodics or acetaminophen rather than nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs, such as over-the-counter brands like Advil or Motrin (ibuprofen) or Aleve (naproxen), as well as prescription brands, may increase the chance of diverticulitis complications.

If you have abscesses, your healthcare provider may:

  • Prescribe antibiotics (for small abscesses)
  • Drain large abscesses
  • Recommend surgery after a large abscess heals (to prevent the abscess from returning)

If your diverticulitis doesn’t improve with less-invasive treatments or if you develop complications, surgery may be recommended to remove part of your colon. This is called a colectomy or colon resection. 

Surgery is usually recommended to treat diverticulitis complications such as perforations, peritonitis, fistulas, and intestinal obstructions.

Recovery From Severe Diverticulitis

As part of your recovery, you may be admitted to the hospital for a couple of days to stay until your symptoms improve and/or you recover from surgery. 

If you have been following a clear liquid diet or have been unable to eat, you will slowly begin to advance your diet (such as to a low-fiber diet and to a normal diet) as directed by your healthcare provider and as tolerated by you.

As you are recovered, you may also be counseled to exercise regularly to help prevent future diverticulitis flare-ups. Your healthcare provider may also recommend a colonoscopy after fully recovering from diverticulitis to rule out colon cancer.


Diverticulitis is inflammation or infection of diverticula in the colon. Severe diverticulitis symptoms include persistent abdominal pain, nausea, vomiting, fever, and constipation. Severe diverticulitis may lead to complications that require immediate medical attention. 

If a diverticulum has perforated (burst), it may cause an increase in the severity of your symptoms, as well as rapid heart rate, dizziness, light-headedness, or weakness. It may also lead to a serious complication known as peritonitis. Other potential complications of diverticulitis include abscess, fistula, and intestinal obstruction.

In the hospital, your healthcare provider will review your medical history, perform a physical exam, and order tests to help accurately diagnose diverticulitis. In some cases, diverticulitis may be treated with antibiotics, pain medication, and bowel rest. However, more severe cases may require surgery.

You may need to recover in the hospital for a short time until your symptoms improve. Your healthcare provider will give you instructions on how to add more foods back into your diet, what medications to take and which ones to avoid, physical activity, as well as any recommended follow-up tests and procedures.

8 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.
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By Brittany Poulson, MDA, RDN, CD, CDCES
Brittany Poulson, MDA, RDN, CDCES, is a registered dietitian and certified diabetes care and education specialist.