What Causes Bad Breath Even After Brushing

Occasional bad breath is a common problem most everyone experiences at some point and is usually remedied with oral hygiene. For patients with chronic halitosis, bad breath persists even after brushing. There are a number of underlying issues that can cause chronic bad breath and some need to be treated by a general practitioner instead of a dental professional.

Causes of Bad Breath

Gum Disease and Tobacco Use

Oral hygiene is the easiest way to prevent dental issues, including bad breath. Without proper brushing and flossing, plaque and bacteria accumulate on the surface and in between teeth and cause bad breath. Gum disease develops when plaque build up calcifies and invades and irritates your gum tissue.

Tobacco use can also cause bad breath even with regular dental hygiene. Smoking causes dry mouth which in turn causes bad breath. It is important to practice proper oral hygiene, even more so if you smoke. Incorporating a tongue scraper to your regular routine can improve your chances of keeping bad breath at bay.

Sinus and Respiratory Infections

Colds, strep throat, bronchitis, and sinus infections can all cause bad breath because of the overproduction of mucus which is a breeding ground for bacteria. Your general doctor can prescribe an antibiotic to treat the infection and bad breath should resolve on its own.


Patients living with diabetes can have a sweet smell to their breath but for those that go into ketoacidosis may have a fecal odor instead of a sweet one. Ketoacidosis is a medical emergency that occurs in patients with type one diabetes and can cause their breath to have a fecal odor from vomiting or dry mouth. It happens when the body produces a high level of ketones, acids in the blood, and requires immediate medical attention and possible hospitalization. Treatment will include insulin therapy, fluid and electrolyte replacement.

Intestinal Obstructions

An intestinal obstruction in the large or small intestine can also make a patient’s breath smell like feces. Anything that the patient consumes if they have an intestinal blockage will not be able to pass into the intestine and well ferment in the digestive tract.

Gastrointestinal Problems

Issues with a patient’s gastrointestinal tract can also lead to chronic bad breath, again a fecal smell. Gastroesophageal reflux disease, or GERD is one such issue. Patients with GERD experience stomach acid backing up into the esophagus and irritating the esophageal lining.

Halitosis can typically be resolved within a couple of weeks if the cause is a short term problem such as GERD or poor oral hygiene. For patients who have bad breath as a result of a more severe condition, treatment for bad breath will depend on the treatment for the underlying condition. Once the medical issue is addressed, your dentist can begin treating bad breath if it does not resolve on its own. If you have chronic bad breath, it is important to speak with your dentist and receive treatment.

What Does Halitosis Smell Like