Diverticulitis: Lower Left Belly Pain, Treating a Flare, and When It's the ER
Diverticulitis usually causes steady pain in the lower left belly with fever. Mild flares can be treated at home; some need the ER. Here's how to tell.
Diverticulitis is inflammation or infection of small pouches (diverticula) in the wall of the colon. It usually causes steady pain in the lower left belly, often with fever, nausea, and a change in bowel habits. It's more common after age 40. A mild flare can often be treated at home with rest, a liquid or low-fiber diet for a few days, and sometimes antibiotics. Severe pain, a high fever, vomiting, or bleeding needs the ER.
Diverticulosis vs. diverticulitis
- Diverticulosis means having the pouches. It's very common with age and usually causes no symptoms.
- Diverticulitis is when one or more pouches become inflamed or infected.
Symptoms
- Steady pain, usually in the lower left belly, that lasts for days
- Tenderness when the area is pressed
- Fever and chills
- Nausea or vomiting
- Constipation or diarrhea
- Bloating
In some people, especially of Asian descent, the pain is on the lower right. Our post on lower right or left belly pain covers other causes.
Treating a mild flare
When a clinician agrees it's safe to treat at home:
- Clear liquids for a day or two, then low-fiber foods, then back to a normal high-fiber diet as you improve
- Rest
- Acetaminophen for pain. Avoid ibuprofen and naproxen, which can raise the risk of complications.
- Antibiotics if the clinician prescribes them
- Follow up if you're not improving in two or three days
Preventing flares
- Eat a high-fiber diet with plenty of fruits, vegetables, beans and whole grains once you've recovered
- Drink plenty of water
- Stay active
- Don't smoke
- Seeds and nuts are fine; they don't cause flares
What urgent care can do
A clinician can examine you, check your vital signs and urine, and decide whether a mild flare can be treated at home or whether you need a CT scan and blood tests at the ER. At an AfterOurs clinic, a standard self-pay visit is $175, and a self-pay in-clinic visit never costs more than $330. We contract with all major commercial and government plans, including Colorado Medicaid and Medicare. See our abdominal pain page and the cost and insurance page.
Go to the ER or call 911 if you have severe or worsening belly pain, a hard or very tender belly, a fever over 101°F with belly pain, vomiting and can't keep fluids down, blood in your stool or rectal bleeding, can't pass stool or gas, or you're older, pregnant or have a weakened immune system with these symptoms.
Where to find us
Four clinics across metro Denver, all ages welcome, se habla español:
- Hampden (Southeast Denver): 8 AM–11 PM daily
- Littleton: 8 AM–11 PM daily
- Thornton: 8 AM–11 PM daily
- Highlands: Mon–Fri 5–11 PM, Sat–Sun 8 AM–11 PM
Walk in, or book online.
Medically reviewed by Peter Martinuzzi, MD
This article is general health information, not medical advice for your situation. If you are worried, come in or book a telehealth visit — and if it is an emergency, call 911.