Bad Breath (Halitosis)
Bad breath is one of those things people hate to bring up, even with their dentist. Maybe someone stepped back a little during a conversation, or a family member finally said something, or you've noticed a stale taste that brushing doesn't touch. You're not alone, and in most cases the source is easy to find and treat.
Bad breath (halitosis) is an unpleasant odor that hangs on beyond normal morning breath or a garlicky lunch. About 9 in 10 cases start in the mouth, mostly from bacteria living in the coating on the back of the tongue and around inflamed gums. It isn't contagious and it's very treatable. Clean your tongue and between your teeth daily. See a dentist if it lasts 2 weeks despite that.
Not sure this is what you have? Answer five quick questions in our mouth spot checker. It compares what you see with more than 40 common conditions and tells you how soon to have it looked at.
- How to check your own breath
- Where is the smell coming from?
- The back of the tongue
- What the common sources look like
- Why does my breath smell like…?
- Bad breath causes
- Bad breath even after brushing
- Morning breath
- Halitosis symptoms
- Worried, but no one else notices?
- How long it lasts
- Bad breath treatment that works
- Remedies: fixing vs. masking
- What a dentist can do
- After an extraction
- Keeping it away for good
- Kids, pregnancy, dentures, cancer care
- When to see us
- FAQ
How to check your own breath
Your nose gets used to your own smell, so you're a poor judge of your own breath. Breathing into a cupped hand doesn't work well either. These checks are more honest:
- The spoon test. Gently scrape the back of your tongue with a clean spoon, wait a few seconds, then smell the spoon. This samples the spot where most odor starts.
- The floss test. Floss between your back teeth and smell the floss. A strong odor points to gum pockets or trapped food in that area.
- The wrist test. Lick the inside of your wrist, let it dry for 10 seconds, and sniff. It's easy, but it mostly samples the front of the tongue, so it can miss odor from the back.
- Ask someone you trust. A partner, parent or close friend is the most reliable test you have. Ask them to tell you plainly, at different times of day.
Where is the bad breath coming from?
Finding the source is most of the battle. A simple trick that doctors and dentists use: close your mouth and breathe out slowly through your nose, then breathe out through your mouth. Have someone you trust smell each one, or use the spoon test for the mouth side.
From the mouth (most people)
Studies of people who go to breath clinics find the mouth is the source about 90% of the time. The main culprits are the coating on the back of the tongue, gum inflammation, or both. Bacteria in those spots break down proteins and give off volatile sulfur compounds, the same gases that make rotten eggs and cabbage smell. See our guides to white tongue and tongue coating and gum disease.
From the nose, sinuses or tonsils
Bad breath from the throat usually means tonsil stones, small, foul-smelling clumps that collect in the pockets of the tonsils. Postnasal drip and sinus infections can also cause a thick, stale odor, especially if the smell comes out of your nose. Sinus trouble sometimes shows up as tooth pain too, which we explain in our post on sinus infections and tooth pain.
From the stomach
Bad breath from the stomach is less common than people think. The valve at the top of the stomach stays closed most of the time, so stomach odor mostly escapes with burps, reflux or vomiting. Reflux can leave a sour taste and smell, especially in the morning, and it can wear down teeth. Our page on acid reflux and your mouth covers that side. Some research links the stomach bacterium H. pylori with bad breath, but the connection isn't settled.
From the rest of the body (rare)
A small share of bad breath comes from compounds that travel in the bloodstream and leave through the lungs. Garlic and onions are the everyday example, which is why brushing doesn't fix garlic breath. Much less often, a body-wide odor goes along with a medical condition such as uncontrolled diabetes, kidney disease, liver disease, a lung infection, or a rare inherited condition. People with these conditions are usually unwell in other ways, and they need a physician, not a stronger mouthwash.
The back of the tongue: the most common source of bad breath
The top of your tongue isn't smooth. It's covered in tiny threadlike bumps, and the spaces between them hold bacteria, dead cells, food and postnasal mucus. The front of the tongue gets scrubbed every time you eat and talk. The back third barely moves against anything, so the coating builds up there. It also has fewer air and saliva currents, which suits the oxygen-avoiding bacteria that make the worst smells.
The good news is that this is the easiest source to fix. A tongue scraper or a toothbrush pulled from back to front once or twice a day removes most of it. If you gag, exhale slowly while you scrape and start a bit farther forward until you get used to it.
What the common sources of bad breath look like
You can't see a smell, but you can often see where it comes from. Stand at a mirror with good light and look for a white or yellowish film on the back of your tongue, red or puffy gums that bleed when you brush, a broken filling or a dark spot where food packs in, and white or yellow specks on your tonsils.
Why does my breath smell like poop, fish or metal?
The type of smell can point toward a cause. It's a clue, not a diagnosis. Most of these have ordinary dental explanations, and the medical ones nearly always come with other symptoms.
| Smell or taste | Common causes | Less common causes | Who to see |
|---|---|---|---|
| Poop (fecal) | Advanced gum disease, an abscess, food trapped under a bridge or in a deep gum pocket, tonsil stones, severe dry mouth | Very rarely, a bowel blockage. That comes with belly pain, swelling and repeated vomiting. | Dentist. Belly pain with vomiting needs the ER. |
| Fish | Recent fish or eggs, poor tongue cleaning | Trimethylaminuria, a rare inherited condition that causes a fishy smell in breath, sweat and urine. Kidney disease can also cause a fishy or ammonia smell. | Dentist first. Physician if no mouth cause is found. |
| Sulfur or rotten eggs | Tongue coating and gum disease (hydrogen sulfide is the main gas), garlic and onions, sulfur burps | Reflux or a stomach upset | Dentist |
| Metal | Usually a taste, not a smell. Bleeding gums, some medicines (certain antibiotics, metformin), iron, zinc or prenatal vitamins, pregnancy | Taste changes after a viral illness, chemotherapy, kidney disease | Dentist for bleeding gums. Ask your physician or pharmacist about medicines. |
| Fruity or nail-polish remover (acetone) | Ketones from fasting or a low-carb (keto) diet, which is harmless | In someone with diabetes, fruity breath with nausea, vomiting, belly pain, fast breathing or confusion can mean diabetic ketoacidosis (DKA), a medical emergency | Physician. If you have diabetes and any of those symptoms, go to the ER or call 911. |
| Ammonia or urine | Dehydration can make breath stronger in general | Kidney disease, usually already known and with other symptoms | Physician |
A musty or sweet smell can go along with serious liver disease, and a sour smell often means reflux or recent vomiting. If you've had a new, strange smell for weeks and your dentist finds nothing in your mouth, that's a good reason to see your physician. It's rarely something serious, but it's worth checking.
Bad breath causes
Most halitosis causes fall into a few groups. Many people have more than one going at once.
In the mouth
- Tongue coating. The most common cause, especially on the back third.
- Gum inflammation and gum disease. Bacteria in the pockets around teeth make a lot of sulfur gas. Gums that bleed when you brush are a giveaway. Early gum inflammation is covered in our gingivitis guide.
- Food traps. Cavities, broken or leaking fillings, gaps between teeth, and spaces under crowns and bridges.
- Dry mouth. Saliva rinses and fights bacteria. Less saliva means more odor. Medicines, mouth breathing, snoring, CPAP leaks, aging and some medical conditions all dry the mouth. Our dry mouth page has more.
- Infections. A tooth abscess, an infected gum flap over a wisdom tooth, a healing extraction site, or trench mouth, a painful gum infection with a very strong odor.
- Dentures, retainers and night guards that aren't cleaned daily or are worn overnight.
Habits and diet
- Smoking, vaping and chewing tobacco
- Garlic, onions, spices, coffee and alcohol
- Skipping meals, fasting or very low-carb diets (ketone breath)
- Not drinking enough water
Outside the mouth
- Tonsil stones and tonsil infections
- Sinus infections and postnasal drip
- Reflux, frequent vomiting and some stomach conditions
- Rarely: uncontrolled diabetes, kidney or liver disease, lung infections, inherited metabolic conditions
Bad breath even after brushing and flossing
This is the most common thing people tell us: "I brush twice a day and use mouthwash, and I still have bad breath." Bad breath with good oral hygiene usually comes down to one of these:
- The tongue isn't getting cleaned, or only the front of it is. Brushing teeth doesn't touch the back of the tongue.
- There's gum disease below the gumline. Floss can't reach the bottom of a deep pocket. Only a professional cleaning, and sometimes deep cleaning, can.
- Something is trapping food. A broken filling, a crown with an open edge, a cavity between teeth, or the space under a bridge.
- Your mouth is dry. Especially overnight, or if you take medicines for blood pressure, mood, allergies or bladder control.
- The mouthwash is the problem. Alcohol rinses mask odor for an hour or so, then dry the mouth and can make it worse.
- It isn't coming from the mouth at all. Tonsil stones and sinus drainage are the usual suspects.
Bad breath right after a dental cleaning is usually short-lived. Gums can be tender and bleed a little for a day or two. If it lasts longer than that, the tongue, tonsils or sinuses are likely the source, and we'll want to look again.
Why does my breath smell so bad in the morning?
Morning breath is normal. Saliva flow drops way down while you sleep, so bacteria have hours to work undisturbed. Sleeping with your mouth open, snoring or using a CPAP makes it worse. It should fade after you brush, clean your tongue, drink some water and eat breakfast.
To get rid of bad breath in the morning, clean your tongue and floss at night, not just in the morning. Keep water by the bed. If you breathe through your mouth at night, it's worth asking your physician about nasal congestion or sleep apnea. Morning breath that doesn't fade by midmorning is no longer just morning breath.
Halitosis symptoms: signs your breath may be off
Since you can't smell your own breath well, these clues help:
- A bad, sour or metallic taste that comes back soon after brushing
- A white or yellow coating on the back of the tongue
- Dry, sticky mouth or thick saliva
- Gums that bleed when you brush or floss
- Floss that smells after you use it
- White specks on the tonsils, or coughing up small smelly lumps
- Postnasal drip or a constant need to clear your throat
- Others stepping back, offering gum, or telling you
Worried about bad breath, but no one else notices?
Some people are sure they have bad breath, yet a dentist and the people close to them can't detect any odor. This is called pseudo-halitosis. It's more common than you'd think. Often a bad taste, a dry mouth, or someone's offhand gesture convinces a person that their breath smells.
When the worry continues even after a checkup and treatment, it's sometimes called halitophobia. It's real distress and it deserves to be taken seriously. We can examine you, look for anything that could cause a taste or odor, and tell you honestly what we find. Treating a bad taste or dry mouth often helps. If the worry is affecting your work or relationships, talking with your physician or a counselor can help too.
How long does bad breath last?
It depends on the cause:
- Morning breath: gone within an hour or two of being up, eating and brushing.
- Food breath (garlic, onion): up to a day or so. Brushing helps the mouth part, but the rest comes from your lungs until your body clears it.
- Tongue coating: noticeably better within a few days of daily tongue cleaning.
- Gum disease: usually improves a lot within a few weeks after a professional cleaning and better home care.
- Dry mouth, tonsil stones, sinus problems: come and go until the cause is managed.
If you've cleaned your tongue and between your teeth every day for 2 weeks and your breath is still bad, it's time for an exam.
Bad breath treatment that works
Real halitosis treatment means removing the bacteria and the places they hide. Do these daily for 2 weeks before judging the results.
- Clean your tongue once or twice a day. Use a tongue scraper or your toothbrush. Start as far back as you can, press lightly, and pull forward. Rinse the scraper and repeat 5 to 10 times. Halitosis experts list this as the first step.
- Clean between your teeth every day. Floss, small interdental brushes, or a water flosser. Interdental brushes are often easier for wider gaps and around bridges.
- Brush for 2 minutes, twice a day, with a fluoride toothpaste, paying attention to the gumline.
- Use a rinse that targets odor, not one that hides it. Rinses with zinc, cetylpyridinium chloride (CPC) or chlorine dioxide help reduce odor gases. Use them after cleaning, as the label directs. The research on rinses is modest, and they work much better alongside cleaning than instead of it.
- Keep your mouth moist. Sip water through the day, chew sugar-free gum to get saliva flowing, and use a humidifier at night if you breathe through your mouth.
- Clean appliances. Take dentures out at night and brush them. Clean retainers and night guards every day.
- Get gum disease and broken teeth treated. No amount of rinsing fixes a deep gum pocket or a leaking filling.
About chlorhexidine
Chlorhexidine is a prescription rinse. It's strong against bacteria, and we sometimes use it for a week or two to get gum inflammation under control. It isn't meant for long-term daily use. Over time it can stain teeth and tongue brown, change how food tastes, and build up tartar.
Bad breath remedies: what fixes it and what only masks it
Most of the bad breath aisle masks odor rather than fixing it. That's fine for a meeting or a date. Just know which is which.
| Product | Fixes or masks? | Things to know |
|---|---|---|
| Tongue scraper | Fixes | Cheap and effective. Plastic or metal both work. Clean it after each use. |
| Floss, interdental brushes, water flosser | Fixes | Removes trapped food and plaque between teeth. Daily use matters more than which tool. |
| Zinc or CPC mouthwash, zinc toothpaste | Helps | Reduces odor gases. Choose alcohol-free. Mouthwash isn't for children under 6 because they may swallow it. Follow the label. |
| Chlorine dioxide rinse | Helps | Breaks down sulfur compounds. Use as directed. |
| Saliva substitutes, dry mouth rinses and gels | Helps if your mouth is dry | Use as often as needed. Look for products made for dry mouth. |
| Sugar-free gum or mints (xylitol) | Mostly masks | Gum does help by boosting saliva. Sugary mints feed cavity bacteria, so skip them. |
| Alcohol-based mouthwash | Masks | Freshens for a short time, then can dry the mouth. Not a good daily choice if you have dry mouth. |
| Breath sprays and strips | Masks | Minutes of cover. Fine in a pinch. |
If you're pregnant, nursing, or giving a mouth rinse to a child, check the label or ask your pharmacist first, and choose alcohol-free.
What a dentist can do for bad breath
Since the mouth is the source most of the time, a dental exam is the right place to start. Here's what we do:
- Ask the right questions. When it's worst, who noticed it, what medicines you take, and whether you have dry mouth, reflux, sinus trouble or snoring.
- Smell and look. We compare mouth and nose breath and check the tongue, gums, tonsils, teeth and any dental work.
- Measure the gums. We check the depth of the pockets around each tooth, which tells us whether gum disease is part of the picture.
- Take x-rays when needed to find cavities between teeth, leaking fillings, infections or bone loss.
- Clean and treat. A professional cleaning, deep cleaning for gum disease, repairing broken fillings or crowns, and treating infections.
- Coach you on technique. We'll show you how to clean your tongue and between your teeth, and which tools fit your mouth.
- Manage dry mouth. We review your medicines with you and can coordinate with your physician if a change might help.
- Prescribe a short course of chlorhexidine when it makes sense.
- Refer you to your physician, an ENT, or a GI doctor if your mouth checks out and the source seems to be elsewhere.
Bad breath after tooth extraction or wisdom teeth removal
Some odor in the first few days after an extraction is normal. There's blood, a healing wound, and you're brushing less around the area. Gentle salt-water rinses after the first day and careful brushing of the other teeth help. Follow our extraction aftercare instructions.
A foul smell or taste that shows up around day 2 to 4 along with pain that gets worse instead of better can mean a dry socket. Swelling, pus, fever or a bad taste that keeps coming back can mean infection. With partly erupted wisdom teeth, an infected gum flap is a common cause of bad breath; see pericoronitis. Call us if you notice any of these.
How to get rid of bad breath permanently
There's no single product or halitosis cure that works for everyone, but most people can keep it away with a few daily habits:
- Clean your tongue every day, especially at night.
- Clean between your teeth every day.
- Drink water through the day and limit alcohol and tobacco.
- Don't skip meals for long stretches. Eating gets saliva moving.
- Get dental cleanings and exams on the schedule your dentist recommends, often every 6 months, sometimes more often if you have gum disease.
- Get broken fillings and loose crowns fixed promptly.
- Treat what's outside the mouth: allergies, sinus problems, reflux and mouth breathing.
Bad breath in kids, during pregnancy, with dentures and during cancer treatment
Children
Kids get bad breath from the same things adults do, plus mouth breathing from big tonsils or allergies. One special case: a very foul smell with discharge from one nostril in a young child can mean something is stuck in the nose. That needs a pediatrician. Help young children brush their tongue, and don't give mouthwash to kids under 6.
Bad breath during pregnancy
Pregnancy hormones make gums swell and bleed more easily, and morning sickness, reflux and a dry mouth can all add to it. After vomiting, rinse with water or a teaspoon of baking soda in a cup of water and wait about 30 minutes before brushing, so you don't scrub softened enamel. Dental cleanings are safe during pregnancy, and the second trimester is often the most comfortable time.
Dentures
Dentures pick up odor and yeast. Brush them every day with a denture cleaner (not regular toothpaste, which scratches), soak them overnight, and leave them out while you sleep. Brush your gums and tongue too. A denture that no longer fits well traps food. Our denture page covers care and relines.
Diabetes
Diabetes raises the risk of gum disease and dry mouth, both big causes of bad breath. Fruity or nail-polish-remover breath with nausea, vomiting, belly pain, fast breathing or confusion in someone with diabetes can mean diabetic ketoacidosis. That is an emergency, so go to the ER or call 911. See diabetes and your mouth.
During chemotherapy or radiation
Cancer treatment can cause dry mouth, mouth sores, yeast infections and taste changes, all of which affect breath. Gentle cleaning, bland rinses and dry mouth care help. Our head and neck cancer dental care page explains how we support people before, during and after treatment.
When to see a dentist about bad breath
Make an appointment if:
- Bad breath lasts 2 weeks even with daily tongue cleaning and flossing
- Your gums bleed, look puffy, or are pulling back from your teeth
- You have a bad taste that keeps coming back
- Food keeps getting stuck in one spot, or a filling or crown feels rough or broken
- Your mouth is dry most of the time
- You see white lumps on your tonsils or keep coughing them up
Get care quickly if:
- You have facial swelling, fever, or pus from the gums, or severe gum pain with a foul smell
- A foul taste and worsening pain show up a few days after an extraction
- You have diabetes and fruity breath with nausea, vomiting, belly pain, fast breathing or confusion. That can be diabetic ketoacidosis, an emergency: go to the ER or call 911
- A fecal smell comes with belly pain, swelling and repeated vomiting (go to the ER)
Bad breath FAQ
Why does my breath smell so bad even though I brush?
Brushing your teeth doesn't clean the back of your tongue or below the gumline, which are the two biggest sources of bad breath. Clean your tongue from back to front and clean between your teeth every day. If the odor is still there after 2 weeks, a dental exam can check for gum disease, broken fillings, dry mouth or tonsil stones.
Why does my breath always stink?
Breath that smells bad all the time usually has a steady source: a heavily coated tongue, gum disease, a chronic dry mouth, or food trapped in a cavity or under a bridge. Less often it's tonsil stones or sinus drainage. A dentist can usually find the source in one visit.
Why does my breath smell so bad in the morning?
Saliva flow nearly stops while you sleep, so odor-causing bacteria multiply overnight. That's normal morning breath. Clean your tongue and floss before bed, keep water nearby, and it should fade after breakfast and brushing. Sleeping with your mouth open or snoring makes it worse.
Why does my breath smell like poop?
A fecal-smelling breath usually comes from heavy bacterial breakdown in the mouth: advanced gum disease, an abscess, food packed in a deep gum pocket or under a bridge, or tonsil stones. It's worth a dental visit soon. Very rarely, it's linked to a bowel blockage, which comes with belly pain, swelling and repeated vomiting and needs emergency care.
Can gum disease cause bad breath?
Yes. Gum disease is one of the two most common causes of bad breath, along with tongue coating. Bacteria in the pockets around the teeth produce sulfur gases, and floss can't reach the bottom of deep pockets. Professional cleaning or deep cleaning usually improves the breath a lot within a few weeks.
How do I get rid of bad breath instantly?
For a quick fix, brush, scrape your tongue, floss, and drink a glass of water. Sugar-free gum and a zinc or CPC rinse help for a few hours. Mints and breath sprays only mask odor for minutes. For lasting results you need to remove the source.
How do I get rid of bad breath permanently?
Clean your tongue and between your teeth every day, stay hydrated, and get regular dental cleanings. Have gum disease, cavities and broken fillings treated, since no rinse can fix those. If your breath is still bad after that, look outside the mouth with your physician: tonsils, sinuses, reflux or a medical condition.
How do I get rid of bad breath from tonsil stones?
Gargle with salt water after meals, keep your mouth moist, and clean your tongue daily. Gentle rinsing with a low-pressure water flosser can loosen stones, but don't poke your tonsils with sharp objects. If stones keep coming back and bother you, an ENT can talk with you about treatments, including removing the tonsils.
Can bad breath come from your stomach?
Sometimes, but less often than people think. The top of the stomach stays closed most of the time, so stomach odor mainly comes up with burps, reflux or vomiting. To get rid of bad breath from acid reflux, treat the reflux with your physician, avoid late meals, and rinse with water after reflux episodes. Most persistent bad breath still comes from the mouth.
Why does my breath taste bad?
A bad taste usually comes from the same sources as bad breath: tongue coating, gum disease, dry mouth, a draining infection, or tonsil stones. Medicines, reflux, sinus drainage and vitamins can also change taste. A metallic taste is often from bleeding gums or a medicine. If it lasts more than a couple of weeks, have it checked.
What is the medical term for bad breath?
The medical term is halitosis, sometimes called oral malodor. Halitosis just means a noticeable, unpleasant breath odor. It's a symptom, not a disease, so the goal is to find and treat the cause.
Which bad breath mouthwash actually works?
Look for an alcohol-free mouthwash with zinc, cetylpyridinium chloride (CPC) or chlorine dioxide, which reduce the sulfur gases that cause odor. Use it after brushing, tongue cleaning and flossing. Alcohol-based rinses can dry the mouth and make breath worse later. Chlorhexidine is a prescription rinse for short-term use only because it stains teeth.
Why does my breath smell like sulfur or rotten eggs?
That rotten-egg smell is hydrogen sulfide and related sulfur gases, made by bacteria living in tongue coating and gum pockets. It's the classic smell of ordinary bad breath, and daily tongue cleaning plus flossing usually cuts it down a lot. Garlic, onions and sulfur burps from the stomach can add to it. If it lasts 2 weeks despite good cleaning, have your gums checked.
Can you have bad breath and not know it?
Yes. Your nose gets used to your own smell, so most people can't judge their own breath. The spoon test (smell a spoon after scraping the back of your tongue) or asking someone you trust is more reliable. The reverse also happens: some people worry about bad breath that no one else can detect.
Bad breath that won't go away?
If you're in the Jacksonville area and your breath hasn't improved with good home care, we're glad to help find the source. It's a common reason people see Dr. Henley, and there's nothing embarrassing about asking. Most of the time we can find it and treat it.
Related conditions
Sources
- Seemann R, Conceicao MD, Filippi A, et al. Halitosis management by the general dental practitioner: results of an international consensus workshop. J Breath Res. 2014;8(1):017101.
- Tangerman A, Winkel EG. Extra-oral halitosis: an overview. J Breath Res. 2010;4(1):017003.
- Kumbargere Nagraj S, Eachempati P, Uma E, et al. Interventions for managing halitosis. Cochrane Database Syst Rev. 2019;12:CD012213.
- Kapoor U, Sharma G, Juneja M, Nagpal A. Halitosis: current concepts on etiology, diagnosis and management. Eur J Dent. 2016;10(2):292–300.
- MedlinePlus Genetics, National Library of Medicine. Trimethylaminuria.
This page is for general education and isn't a diagnosis. Every mouth is different. If you have a sore you're worried about, see your dentist or physician. Photos marked Wikimedia Commons are used under their listed licenses and may have been cropped or resized.