There are numerous possible reasons for breath that smells like poop. These include poor oral hygiene, a dental infection, prolonged vomiting, bowel obstruction, and more.

There are several potential causes of a feces-like odor on the breath, ranging from minor to more serious.

In this article, we provide detailed descriptions of the six most common causes. We also discuss when to see a doctor.

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Halitosis is the medical name for severe bad breath. In most cases, it occurs due to conditions affecting the mouth, such as gum disease. It may be a result of changes in the bacteria that naturally live in the mouth, which can produce gases.

Things that may contribute to halitosis include:

Cleaning the teeth with a brush and toothpaste twice daily and using antibacterial mouthwash may help in cases where the cause is infrequent cleaning.

Stopping smoking and seeking treatment for any oral conditions may also be appropriate.

The sinuses are air-filled passages in the face. If they swell up they can trap fluid inside, leading to pain and potentially, unpleasant breath.

Additional symptoms of a sinus infection include:

Most sinus infections occur due to viruses, not bacteria. As a result, most get better on their own when the virus goes away. If a doctor suspects the infection is bacterial, they may prescribe antibiotics.

Gastroesophageal reflux disease (GERD) is when a person frequently experiences acid reflux. This involves stomach acid backing up into the food pipe, or esophagus.

GERD can cause bad breath when the stomach acid mixes with food and possibly bacteria. Additional symptoms of GERD include:

Treatment depends on the cause, but may include dietary, lifestyle, or medication changes. There are also drugs that can reduce the production of stomach acid. In some cases, people may undergo surgery.

GERD can lead to complications without treatment. Anyone who experiences frequent acid reflux should seek medical care.

An abscessed tooth is a severe dental infection. It occurs when the pulp inside a tooth dies. If bacteria get inside the tooth, this can result in an infection that affects the nearby gum or bone. The symptoms may include:

  • bad breath
  • swelling in the gums, face, or jaw
  • pain
  • a tooth that feels tender, loose, or changes color

Not all abscesses are painful, which is why anyone who notices a change in the color of a tooth or swelling in the face should speak with a dentist. Without treatment, a person may also feel generally unwell or have a fever.

The treatment is often a root canal procedure, which removes the dead tissue from inside the tooth, while keeping the tooth intact. Other options may include endodontic surgery, or tooth removal.

Anyone who has been vomiting for an extended period may find that their breath smells sour or unpleasant. The odor may occur due to:

  • the acidic contents of the stomach passing through the mouth
  • the bacteria or virus causing the vomiting
  • dehydration, which may lead to a dry mouth

Vomiting has many potential causes, such as norovirus, food poisoning, pregnancy, or some chronic conditions. Staying hydrated, wherever possible, is important to prevent dehydration.

If a person keeps vomiting for several days, or this symptom keeps coming back, they should speak with a doctor. People and children with severe dehydration who cannot keep fluids down need immediate medical attention.

A bowel obstruction occurs when the small or large intestine becomes blocked so that food can no longer move through the digestive system.

When a person has a bowel obstruction they can develop severe constipation. Stool may accumulate and block the intestines, moving up the gastrointestinal tract. In severe cases, a person may vomit feces.

Causes of bowel obstructions can include:

In addition to bad breath and constipation, a person with a bowel obstruction may experience:

  • abdominal pain
  • bloating
  • an inability to pass gas
  • nausea
  • a rapid heart rate
  • vomiting

Bowel obstructions are serious and sometimes life-threatening. Anyone who suspects that they have an obstruction should seek immediate medical care.

After conducting a physical exam, a doctor will likely order imaging, such as a CT scan, to have a better view of the bowels and determine the cause of any obstruction.

It may be necessary to insert a tube through the nose into the digestive tract to remove excess gas from the intestines and stomach. This can alleviate symptoms and may eliminate the need for surgery.

Severe bowel obstructions may require surgery to remove the obstruction. A doctor may also have to remove a section of bowel, in some cases.

Anyone with unpleasant breath that persists even when a person regularly brushes their teeth should speak with a doctor or dentist. It could be a sign of an underlying medical condition that needs treatment.

A person should get emergency help if they:

  • are in severe pain
  • have facial swelling
  • have signs of dehydration, such as a dry mouth, lack of urine, dark urine, or extreme thirst
  • have a high fever
  • could have a bowel obstruction
  • have vomited feces
  • become confused or delirious
  • lose consciousness

Breath that smells like poop can be a sign of a medical condition, such as halitosis, a tooth abscess, GERD, or a bowel obstruction. If this symptom persists and maintaining good oral hygiene does not help, a person should speak with a doctor.