Bad Breath (Halitosis)

Medically Reviewed on 5/23/2023

What is bad breath?

Halitosis, or bad breath, can be cured with treatment of the underlying causes.
Halitosis, or bad breath, can be cured with the treatment of the underlying causes.

The definition of bad breath, or halitosis, is an unpleasant smell coming from the mouth. Halitosis can occur on occasion, or it can be a chronic condition. It may be caused by foods a person eats, poor oral hygiene, diseases, or other factors.

What are the possible causes of bad breath?

There are many risk factors and causes for halitosis, and even healthy people have bad breath on occasion.

Some 12 common causes of halitosis include the following:

  • Food: Food is a primary source of bad odors that come from the mouth. Some foods, such as garlic, onions, spicy foods, exotic spices (such as curry), some cheeses, fish, and acidic beverages such as coffee can leave a lingering smell. Most of the time the odor is short-lived.
    • Other foods may get stuck in the teeth, promoting the growth of bacteria and dental plaques, which causes bad breath odor.
    • Low carbohydrate diets may also cause "ketone breath." These diets cause the body to burn fat as its energy source.
    • The end-product of making this energy is ketones, which cause a fruity acetone-like odor on the breath when exhaled. This fruity odor in a diabetic might indicate uncontrolled blood sugars.
  • Tobacco products:
  • Poor oral health: When a person does not brush or floss his/her teeth regularly, food particles remaining in the mouth can rot and cause bad odors.
    • Poor dental care can lead to a buildup of plaque in the mouth, which causes an odor of its own. Plaque buildup on the teeth can also lead to an unhealthy condition called periodontal (gum) disease. When plaque hardens, it is referred to as tartar (calculus).
    • Tartar holds bacteria that can irritate the gums and lead to gum disease. The mild form of gum disease is called gingivitis; if gingivitis is not treated, it can advance to periodontitis.
  • Health problems:
  • Dry mouth: Also called xerostomia, dry mouth can also cause bad breath. Saliva helps moisten and cleanse the mouth, and when the body does not produce enough saliva, bad breath may result.
    • A dry mouth may be caused by salivary gland problems, connective tissue disorders (Sjögren's syndrome), medications, or breathing through the mouth.
  • Allergies: Many medications used to treat allergies can cause dry mouth, another cause of halitosis.
  • Mouth infections: Cavities, gum disease, or impacted teeth may cause bad breath.
  • Dentures or braces:
    • Food particles not properly cleaned from appliances such as braces can rot or cause bacteria and odor.
    • Loose-fitting dentures may cause sores or infections in the mouth, which can cause bad breath.
  • Medications:
    • Many medications, including antihistamines to treat allergies and diuretics, can cause dry mouth (see above), which can cause bad breath.
    • Other medications that may lead to bad breath may include triamterene (Dyrenium) and paraldehyde.
  • "Morning breath": Bad breath in the morning is very common. Saliva production nearly stops during sleep, allowing odor-causing bacteria to grow, and causing bad breath.
  • Pregnancy:
    • Being pregnant in itself does not cause bad breath, but nausea and morning sickness common during pregnancy may cause bad breath.
    • In addition, hormonal changes, dehydration, and eating different foods due to cravings may also contribute to bad breath during pregnancy.
  • Other causes of bad breath:
    • Objects stuck in the nose (usually in children),
    • alcoholism, and
    • large doses of vitamin supplements may also cause bad breath.

What signs and symptoms may be associated with bad breath?

It is generally simple how to tell if you have bad breath. Others may notice someone has halitosis before the person does, so another person may tell him or her about their bad breath or give them a larger-than-normal personal space. The most obvious sign or symptom of bad breath is noticing an unpleasant smell coming from the mouth.

Other signs and symptoms of bad breath include:

  • Unpleasant or sour taste or changes in taste
  • Dry mouth
  • A coating on the tongue

What healthcare specialists diagnose and treat halitosis?

The first stop when you have halitosis is usually your dentist. If your dentist determines you have a healthy mouth, you will likely be referred to a physician to look for an underlying health problem.

  • If you have periodontal disease, you may see a periodontist, a dentist who specializes in gum disease and dental implants.
  • If you have braces, it's like your bad breath is caused by food getting stuck in them. You may see your orthodontist for an adjustment.
  • Bad breath in babies or young children may be a sign of infection or undiagnosed medical problems. Consult a child's pediatrician or dentist if an infant or young child has bad breath.

When should someone see a healthcare professional about bad breath?

If proper oral hygiene does not get rid of bad breath, see a dentist or doctor for a diagnosis if bad breath is accompanied by the following:

Also see a doctor or dentist if bad breath develops after taking a new medication, after recent dental surgery, or if any other symptoms develop that are of concern.

How do healthcare professionals diagnose halitosis?

You have halitosis if you have bad breath, and a doctor is not needed to diagnose the condition. However, if your bad breath is chronic, if it does not go away with proper oral hygiene, or if you have other symptoms, you will need to see a doctor or dentist to diagnose the underlying cause.

A doctor or dentist will examine your mouth to look for signs of gum disease, dry mouth, or infections that may be the cause of your bad breath.


What causes tooth decay? See Answer

How do you treat bad halitosis?

Treatment of bad breath depends on the cause.

The American Dental Association recommends the following:

  • Brush and floss teeth regularly. Remember to brush the tongue, too, to remove bacteria from its surface. Brushing the tongue can help with bad breath caused by foods a person has eaten.
  • See a dentist regularly for checkups and to ensure dentures or braces are properly fitted and cleaned (and clean dentures thoroughly each night).
  • Quit smoking or using chewing tobacco.
  • Sugarless gum and sugar-free candy can also keep the mouth from drying out.
  • Keep the mouth moist by drinking water and chewing sugarless gum or sugar-free hard candy to stimulate the production of saliva. Eat a diet of foods that need to be thoroughly chewed to keep saliva flowing. Foods that require a lot of chewing, such as apples or carrots, are good options.
  • Over-the-counter mouthwash can help kill bad breath-causing bacteria and may temporarily mask bad breath odors, but it may not treat the underlying cause.

Keep the mouth moist by drinking water and chewing sugarless gum or sugar-free hard candy to stimulate the production of saliva. Mouthwash may temporarily mask bad breath odors, but it may not treat the underlying cause.

Natural remedies used in the treatment of bad breath include chewing on mint or parsley.

Other treatments for halitosis may include:

  • If bad breath is due to a health problem such as a sinus infection, diabetes, acid reflux (gastroesophageal reflux disease, or GERD), etc., then the underlying medical issue needs to be treated.
  • If bad breath is a side effect of taking a medication, discuss with a health care professional whether other options for medication can be taken. Never stop taking a medication without first consulting your health care professional.

For patients who suffer from dry mouth (xerostomia), artificial saliva may be prescribed by a dentist.

What products can be used to eliminate or mask bad breath?

Bad breath that is due to simple causes such as foods may be more easily masked or eliminated than bad breath due to medical conditions, infections, or medication side effects.

There are some things a person can do to eliminate or at least temporarily mask bad breath.

  • Good oral hygiene, such as brushing the teeth and tongue and flossing, keeps the mouth healthy and can often get rid of bad breath, at least in the short term.
  • Mouthwash may temporarily mask bad breath and can help with oral hygiene.
  • Chewing sugarless gum or sucking on sugar-free mints may temporarily mask bad breath odor.
  • For more serious cases of bad breath, dentists can prescribe special toothpaste and mouthwash that can improve the symptoms of bad breath.

What is the prognosis for people with halitosis?

Most of the time, bad breath can be cured and prevented with proper oral hygiene. It is rarely life-threatening, and the prognosis is good. However, bad breath may be a complication of a medical disorder that needs to be treated.

Medically Reviewed on 5/23/2023
Rosenberg, Mel. "Bad Breath." September 2019. <>.