Persistent Bad Breath

In plain English

What persistent bad breath usually means

Everyone has stale breath on waking or after garlic, onions or coffee, and that kind passes with brushing and time. Persistent bad breath, also called halitosis, is different: an odor that returns soon after cleaning, lasts for weeks, and is often noticed by other people before you notice it yourself. In most cases the source is in the mouth. Bacteria living on the back of the tongue, under the gum line and in places a brush does not reach break down proteins and release sulfur gases, which carry the characteristic smell. Anything that gives those bacteria more shelter or less saliva to wash them away makes it worse. A smaller share of cases originate in the tonsils, nose and sinuses, or further down in the digestive system. Because lasting odor so often points to gum disease or decay that causes no pain, it is worth having checked. See a dentist within 2 to 4 weeks if careful home care does not help, and sooner if you also have pain, swelling, bleeding gums or a constant bad taste.

Poor oral hygiene

Plaque and food left between the teeth, and especially the coating that builds on the back of the tongue, are the most common sources of odor. The breath usually improves noticeably right after thorough cleaning and tongue brushing, then fades again if the routine slips.

Gum disease

Deep pockets between gum and tooth hold bacteria that a brush and floss cannot reach, producing an odor that cleaning at home barely changes. Gums that bleed, look red or have receded, and a persistent unpleasant taste, are common companions. It is usually painless.

Tooth decay or infection

An open cavity, a broken filling or a failing crown can trap decaying food, and an infected tooth may leak pus into the mouth. The smell or taste often seems to come from one area. Pain, a gum bump or swelling alongside it needs a prompt dental visit.

Dry mouth

Saliva continually rinses the mouth, so when the flow drops, as it does during sleep, with mouth breathing, with many medications or with some health conditions, odor builds. A sticky feeling, thick saliva, frequent thirst and breath that is worst in the morning suggest this.

Tonsil stones

Small whitish or yellow lumps of hardened debris can form in the crevices of the tonsils and smell strongly. People may notice a sensation of something caught in the throat or cough one up. A dentist can often see them and may suggest an ear, nose and throat doctor.

Digestive issues

Acid reflux can bring stomach contents and sour odor up toward the mouth, often with heartburn or a bitter taste. Odor from the digestive system is less common than odor from the mouth and is usually considered by a doctor after dental causes have been ruled out.

What a dentist does about it

A dentist will usually ask how long the odor has been present, who has noticed it, what your cleaning routine is, what medicines you take, and whether you have dry mouth, reflux, sinus trouble or snoring. The examination looks at the tongue coating, the gums and pocket depths, any decay or defective fillings and crowns, signs of infection, saliva flow and the tonsils. X-rays may be taken to find decay or bone loss that cannot be seen directly. Treatment is aimed at whatever is found: a professional cleaning or deep cleaning for gum disease, repair of decayed or leaking teeth, treatment of an infection, and advice on tongue cleaning and dry mouth. When the mouth is healthy and the odor persists, the dentist typically refers you to a doctor to look at the throat, sinuses or digestion.

Until you can be seen

A thorough routine is worth trying first, with the understanding that it reduces odor without showing what is behind it. Brush twice daily and include the tongue, reaching as far back as is comfortable. Floss daily, use an antibacterial mouthwash as the label directs, and stay hydrated. Chewing sugar-free gum stimulates saliva, and avoiding strong-smelling foods helps in the short term. If the odor is unchanged, see a dentist within 2 to 4 weeks, since mouthwash and gum can cover a problem that keeps progressing. Bad breath with tooth pain, a swollen gum or a foul taste should be seen promptly, and facial swelling with fever, or any trouble breathing or swallowing, means 911 or the ER.

Note — Timing

When to See a Dentist

Table 1 — Possible causes

Possible Causes of Persistent Bad Breath

1. 01Poor oral hygiene
2. 02Gum disease
3. 03Tooth decay or infection
4. 04Dry mouth
5. 05Tonsil stones
6. 06Digestive issues

Table 2 — Home remedies & self-care

Home Remedies & Self-Care

These may help manage symptoms temporarily while waiting for professional care.

• 01Brush twice daily including tongue
• 02Floss daily
• 03Use antibacterial mouthwash
• 04Stay hydrated
• 05Chew sugar-free gum
• 06Avoid strong-smelling foods

Table 3 — Common treatments

Common Treatments for Persistent Bad Breath

These dental procedures are commonly used to treat persistent bad breath.

Table 4 — Common questions

Frequently Asked Questions About Persistent Bad Breath