Some potential causes of a bad taste in the mouth include tooth cavities, infections, acid reflux, and pregnancy. Because there are so many potential causes, a person may need to consult a doctor or dentist for a diagnosis.

An occasional bad taste in the mouth may be due to eating certain foods or forgetting to brush the teeth. However, when a person cannot get rid of the taste by rinsing and brushing, it may signify a medical condition.

Read on to learn more about the causes and treatments of a persistent bad taste in the mouth.

The medical term for a bad taste in the mouth is dysgeusia. Dysgeusia can vary from person-to-person. The bad taste may be:

  • bitter
  • metallic
  • sour
  • salty
  • sickly sweet

Below are some of the things that may cause a persistent bad taste in the mouth. However, this is not a comprehensive list. People can get a diagnosis from a doctor or dentist.

Dental problems

Dental health issues can contribute to a lingering bad taste in the mouth. This may be the result of:

  • oral hygiene issues
  • cavities
  • abscesses
  • gum disease

Other potential symptoms the root cause may be dental include:

  • bleeding gums
  • pain, redness, or swelling in the gums
  • painful or sensitive teeth
  • bad breath

People with these symptoms need to speak with a dentist. Flossing and brushing regularly and having regular dental check-ups can help prevent these conditions.

Dry mouth

A dry or sticky mouth can sometimes occur alongside an unpleasant taste or bad breath. This can happen because saliva helps maintain oral health. Without enough saliva, bacteria and food particles may produce a bad smell or taste.

A dry mouth may occur due to:

  • dehydration
  • smoking
  • certain medications
  • medical conditions affecting the salivary glands

Some medical conditions, including nerve damage and diabetes, can also lead to a lack of saliva.

Acid reflux

Acid reflux occurs when stomach acid travels upward through the esophagus, or food pipe. A sour taste in the mouth is a common symptom of acid reflux.

Other symptoms include:

  • burning or pain in the stomach, which is known as heartburn
  • a feeling of liquid coming back up the food pipe
  • bad breath
  • nausea
  • sore throat
  • cough
  • hoarse voice

Oral thrush

Oral thrush is a fungal infection in the mouth. Symptoms include:

  • a bad taste in the mouth
  • a cottony feeling in the mouth
  • white sores on the tongue or inner cheeks
  • cracking at the corners of the mouth
  • a loss of taste
  • difficulty eating or swallowing
  • irritation or pain under dentures
  • pain

People taking antibiotics, children, older adults, and those with compromised immune systems are more likely to develop oral thrush, but it can occur in anyone.

Respiratory infections

Infections in other parts of the body, such as the sinuses, tonsils, airways, and middle ear, can also cause an unpleasant metallic taste in the mouth. This includes infections with SARS-CoV-2, the virus that causes COVID-19.

People with these infections may also have:

  • a sore throat
  • headache
  • nasal or sinus congestion
  • a runny nose
  • earache
  • fever

Nutrient deficiencies

Deficiencies in certain vitamins and minerals may affect taste, oral health, or both. This could lead to a bad taste in the mouth.

According to a 2024 review of previous research, some deficiencies that may affect the sense of taste include the following:

Hormonal changes

Hormonal changes in early pregnancy can affect the sense of taste and smell. Many report a metallic taste in the mouth, but it usually disappears as the pregnancy progresses.

Hormonal changes relating to menopause may also cause dry mouth, which may lead to changes in taste.


Many medications can affect a person’s sense of taste. Certain types of the following medications may lead to a bad taste in the mouth:

Medications may cause dry mouth, which can also change a person’s sense of taste or cause bad breath.

People can check the drug leaflet for information on whether changes in taste are a common side effect of that drug. A person should not change the dosage or schedule or stop taking a medication without first consulting a doctor.


Hepatitis is inflammation of the liver. It can occur for a range of reasons, such as viruses or chronic alcohol consumption. The symptoms include:

  • yellowing of the eyes or skin, or jaundice
  • abdominal pain
  • nausea or vomiting
  • fatigue
  • dark urine
  • appetite loss

In acute cases, hepatitis can get better on its own, but the disease can also become chronic. With the chronic form, a person can develop fetor hepaticus, which refers to bad breath due to liver damage.

When the liver has scarring, it cannot filter substances from the body as it should, which may result in breath that smells sweet, musty, or like sulfur.

Anyone who suspects they could have hepatitis needs to contact a doctor.

Cancer therapies

Chemotherapy and radiation may cause an unpleasant taste in the mouth. The taste may be metallic or sour.

Neurological conditions

Neurological conditions may affect saliva production, a person’s sense of taste, or both. Conditions that may cause a bad taste in the mouth include:


There is an association between diabetes mellitus and taste disorders, including having a bad or salty taste in the mouth.

Other possible symptoms of diabetes include:

  • frequent urination, especially at night
  • feeling thirsty
  • tiredness
  • slow wound healing
  • unintentional weight loss
  • blurry vision

Chronic kidney disease

A 2020 study notes that people with chronic kidney disease (CKD) often experience changes in taste. In a 2021 study of people with end stage CKD, the changes participants most commonly reported were a metallic, bitter, or bland taste. However, taste alterations can occur at any stage of the illness.

Otherwise, early stages of CKD have no symptoms. Doctors often discover it via routine blood or urine tests.

Learn more about CKD, its stages, and its symptoms.

Treatment for a lingering bad taste in the mouth depends on the cause. A doctor can identify the underlying condition and recommend the best treatment.

To make a diagnosis, a doctor may take a full medical history and inquire about other symptoms. They may also need to order tests.

For some causes, such as pregnancy, treatment is not necessary. Viral infections can also clear up without treatment. If a cancer therapy is causing the taste, it may go away as the treatment finishes.

For other causes, the treatment may include the below.

Adjusting medications or supplements

If a medication or supplement is responsible for the bad taste, a doctor may suggest an alternative or change the recommended dosage.

A person should not alter, start, or stop medications without consulting a doctor first.

Addressing medical conditions

Treating any underlying conditions may also reduce a bad taste in the mouth.

For example, if a person has a dental condition, a dentist may recommend medications or procedures to address it. If the cause is a nutrient deficiency, a doctor may suggest dietary changes or supplements.

Other causes, such as hepatitis or neurological conditions, may require more ongoing management to reduce the symptoms.

Home remedies may reduce the discomfort of having a bad taste in the mouth. However, a person may still need medical treatment alongside this.

Some ways to reduce the bad taste may include:

  • brushing and flossing the teeth daily
  • chewing sugar-free gum to encourage the production and movement of saliva
  • drinking enough water each day
  • quitting smoking, if applicable
  • limiting or avoiding the intake of alcohol and caffeine
  • cutting down on added sugars, as this can contribute to oral thrush
  • avoiding acid reflux triggers, such as fatty or spicy foods

Many things can cause a bad taste in the mouth, from minor infections to medications and chronic conditions. Because there are so many causes, people with persistent changes in their sense of taste need to consult a doctor or dentist for advice.

In the meantime, several home remedies may provide temporary relief from a bad taste in the mouth, such as regular brushing and flossing, chewing sugar-free gum, or quitting smoking.

These are not substitutes for medical care. A person needs to speak with a medical professional for a diagnosis and effective treatment options.