14 Common Diverticulitis Symptoms

2. Diarrhea

Diarrhea can occur during diverticulitis when inflamed pouches in the colon irritate the bowel lining. This irritation can disrupt normal movement of waste and reduce the colon’s ability to absorb water, leading to loose or watery stools.

You may notice more frequent or sudden urges to pass stool. In some cases, diarrhea alternates with constipation as the digestive tract responds to ongoing inflammation. Abdominal cramping, bloating, or discomfort may occur at the same time.

Diarrhea during a flare may also signal infection or increased inflammation in the affected area of the colon. Because frequent stools can cause fluid loss, staying hydrated is important to help prevent dehydration.

If diarrhea lasts longer than a few days or occurs with severe pain or fever, seek medical care. Further evaluation may be needed to check for infection or complications and to guide treatment that supports healing of the colon.

3. Constipation

Constipation is a common symptom you may experience during an episode of diverticulitis. Inflamed pouches in the colon can slow down food and waste movement, resulting in less frequent and more difficult bowel movements.

You may notice increased straining, smaller stools, or a feeling that your bowels are not fully empty. In some cases, constipation alternates with diarrhea as the inflamed colon reacts unpredictably. Lower abdominal pain or cramping often occurs alongside these changes.

Once symptoms begin to improve, simple steps can help ease constipation. Drinking enough water supports digestion, and gradually increasing fiber intake can soften stool and promote regular bowel movements. Adding fiber slowly helps reduce gas or bloating.

In some situations, a stool softener or bulk-forming laxative may be recommended to make bowel movements more comfortable. If constipation persists for several days or occurs with severe pain, fever, or vomiting, seek prompt medical attention.

4. Bloating in the Belly

Bloating is a common and uncomfortable symptom during diverticulitis. When the diverticula become inflamed, gas or stool can build up in the large intestine. This pressure can make your belly feel full or stretched, even if you have eaten very little.

Your abdomen may look swollen or feel tight to the touch. Some people say the bloating comes and goes throughout the day, while others feel it more after meals. Trapped gas can cause mild cramps or pressure in the lower abdomen, often on the left side.

This bloating often occurs along with other bowel changes, such as constipation or diarrhea. When waste does not move smoothly through the colon, gas can become trapped and worsen the sensation. Drinking enough fluids and eating smaller, balanced meals may help your digestive system function more evenly. If bloating becomes constant or increasingly painful, it may signal worsening inflammation.

5. A Fever

A fever can develop when diverticulitis causes infection or inflammation in the intestine. This happens because your body activates its immune response to fight bacteria and limit the spread of infection. A mild fever may appear at first and rise as the inflammation becomes more severe.

Fever is often one of the earliest signs that diverticulitis is worsening. You may also notice chills, sweating, or fatigue along with it. These changes can happen quickly as your immune system tries to control the problem inside your colon.

If your temperature stays above 100.4°F (38°C) or keeps returning, it usually means the infection is still active. While rest and fluids may ease discomfort, a persistent or high fever needs medical attention.

Medical evaluation may include blood tests to check for signs of infection or inflammation. If tests show signs of infection, treatment may include antibiotics or other supportive care to control the inflammation and help reduce the fever.

6. Abdominal Pain and Tenderness

You will likely notice abdominal pain as one of the first signs of diverticulitis. It usually begins in the lower left side of the belly, where diverticula most commonly form. The pain may start suddenly and can last for several hours or continue for days, depending on the level of inflammation.

The discomfort may feel steady at first and become sharper or more localized as irritation or infection increases. Many people notice that the pain worsens with movement, coughing, or eating, and the area may feel tender when touched. Lying still can sometimes help ease the discomfort.

As pressure builds in the colon, symptoms may change. Pain can ease slightly after a bowel movement if gas or stool is released, but in more severe cases, the discomfort does not improve. Bloating, changes in bowel habits, or difficulty passing gas may occur at the same time.

7. Gas

You may notice increased gas during an episode of diverticulitis. The pouches in your colon can trap air and waste, slowing digestion and allowing gas to build up. This often leads to bloating and discomfort, especially on the lower left side of the abdomen.

Gas may come with a feeling of fullness even after eating small meals. Some people notice more frequent gas or increased pressure in the lower belly, which can worsen abdominal pain during flare-ups. Certain foods can intensify gas symptoms.

Common triggers include beans, onions, cabbage, broccoli, and carbonated drinks. During recovery, your doctor may recommend resting your bowels. This usually begins with clear liquids, followed by a gradual reintroduction of food.

Once you feel better, adding more fiber to your meals can help reduce constipation, which lowers gas buildup over time. Keeping track of what you eat can help you identify which foods cause problems. Writing down your meals and symptoms helps you see patterns.

8. Bloody Stools

When diverticulitis develops, one or more small pouches in the colon can become inflamed or infected. This irritation may affect nearby blood vessels and sometimes cause bleeding inside the intestine. You might notice red or maroon-colored blood mixed with your stool or visible on toilet paper after a bowel movement.

The amount of blood can vary. Some people see only small streaks, while others notice darker or more noticeable discoloration in the stool. The bleeding often comes from small blood vessels near the swollen pouch and may stop on its own, but it should not be ignored.

You may also notice changes in stool texture or appearance, such as looser stools or the presence of mucus. These changes occur because inflammation in the colon can interfere with normal bowel movement and stool formation. If bleeding happens more than once or increases in amount, medical evaluation is important.

9. Nausea

Nausea can occur during a diverticulitis episode because inflammation in the colon disrupts normal digestion. When the bowel is irritated, the movement of food and gas slows, which can trigger a sick or unsettled feeling in the stomach. Nausea often appears alongside other symptoms such as abdominal pain, fever, or loss of appetite.

This feeling may develop early in a flare-up or occur after eating, especially if swelling or infection makes digestion more difficult. In more severe cases, nausea may progress to vomiting. Resting the digestive system with clear fluids for a short period can sometimes help reduce discomfort.

As treatment begins and inflammation improves, nausea usually lessens. Supportive care may include staying hydrated, making temporary diet adjustments, or using medications to control infection and relieve stomach upset. These measures support your colon as it recovers and allow you to resume eating more comfortably.

10. Loss of Appetite

Loss of appetite is common during a diverticulitis flare-up. Pain, nausea, and bloating can make eating uncomfortable or unappealing. When infection is present, your body may also shift energy toward healing rather than digestion, which further reduces hunger. This symptom often appears alongside fever and fatigue.

You may feel full after only a few bites or notice that food no longer sounds appealing. Appetite changes can come and go as inflammation in the colon increases or settles. Eating less during a flare-up can lead to low energy or dehydration, causing weakness or light-headedness if your body does not get enough fluids or nutrients.

Drinking clear liquids and choosing gentle foods such as soups or mashed vegetables can help maintain nourishment until appetite improves. While a reduced appetite is common during illness, seek medical care if it persists or worsens along with pain, fever, or vomiting.

11. Urination Problems

You may notice problems with urination when diverticulitis causes inflammation near the bladder. The colon sits close to the urinary system, and swelling or infection in this area can irritate or press against the bladder, interfering with normal urination and increasing discomfort during daily activities.

You may feel the urge to urinate more often or notice pain or burning when you do. Some people also experience persistent pressure in the lower abdomen that does not ease after emptying the bladder. In rarer cases, infection may spread to the bladder, leading to cloudy or foul-smelling urine or recurrent urinary symptoms.

If a fistula forms, which is an abnormal passage between the colon and bladder, stool or gas may leak into the urinary tract and cause repeated urinary infections. Management usually involves medical treatment, and surgery may be needed to repair the affected tissues and prevent further complications.

12. Fistula

A fistula is an abnormal tunnel that connects your colon to another part of your body, such as the bladder, small intestine, vagina, or skin. In diverticulitis, ongoing inflammation or infection can weaken the colon wall and allow this tunnel to develop. This connection allows gas, stool, or bacteria to move where they should not, which may cause new or unusual symptoms.

Symptoms depend on where the fistula connects. You may notice air or discharge in your urine, pain during urination, or a strong odor. Some people experience leakage of stool or fluid through the vagina or skin. These signs can be confusing because they may not seem related to the digestive system at first.

Doctors usually diagnose a fistula using imaging tests, such as a CT scan, which help identify the location of the abnormal passage. In most cases caused by diverticulitis, surgery is needed to repair or remove the damaged section of the colon.

13. Risk Factors

Your chances of developing diverticulitis increase with age. The condition is most common in people over 50, as the walls of your colon can weaken over time. Aging may also slow digestion and lead to increased pressure inside the colon.

Genetics can also play a role. If one of your close relatives had diverticulitis, you may face a higher risk. Studies show that identical twins are more likely to share this condition than non-identical twins.

Lifestyle factors further affect risk. Diets low in fiber and high in processed foods can make bowel movements harder, increasing strain on the intestines. Not drinking enough water or being physically inactive may add to this pressure.

Other factors include smoking, excess body weight, and frequent use of certain pain relievers such as non-steroidal anti-inflammatory drugs, which can irritate the colon lining. People with weakened immune systems or chronic health conditions may also be more likely to develop severe diverticulitis.

14. Complications

When diverticulitis becomes severe or you do not treat it quickly, it can lead to several health problems. Infection or inflammation can affect nearby tissues or organs in your abdomen and cause these complications.

A common issue is abscess formation, which develops when infected fluid collects near the inflamed area. You may feel constant pain, fever, or chills if this occurs. In some cases, a perforation or small tear can form in your bowel wall, allowing bacteria to escape into the abdomen and cause a serious infection called peritonitis.

Another possible problem is bowel obstruction. Ongoing inflammation or scar tissue can narrow the intestine and block the normal passage of waste. This may lead to cramping, bloating, nausea, or vomiting. If the blockage becomes complete, surgery may be required to remove the affected section of the bowel.

Diverticulitis can also cause bleeding when a blood vessel near a diverticulum breaks. This bleeding is often painless but can be heavy, leading to blood in the stool, weakness, or dizziness from blood loss. Hospital care may be needed for monitoring, fluids, or blood transfusion.

In rare cases, an infected pouch can form a fistula, which creates an abnormal connection between the colon and another organ, such as the bladder or skin. This can cause repeated infections or unusual discharge.