What Causes a Metallic Taste in Your Mouth?

A metallic taste in your mouth, known as dysgeusia, is often related to your sense of smell or taste buds. Sinus infections, gingivitis, and oral injuries are some common causes. Other causes have nothing to do with the mouth at all.

Sometimes the cause can be more serious, including diabetes, dementia, or kidney failure. In these cases, a metallic taste would usually be just one of several symptoms. A metallic taste can also be the first sign of anaphylaxis, a serious allergic reaction.

This article offers several explanations for what causes a metallic taste in the mouth. It also covers when it's time to consult a healthcare provider, and what steps you can take to minimize the taste in the meantime.

Gum Disease or Poor Oral Health

Gingivitis or periodontal disease often result from poor oral hygiene. "Poor" means forgoing regular dental check-ups and not brushing or flossing regularly. These habits can leave a metallic taste in your mouth.

Often, the "metal mouth" sensation is caused by bleeding gums—a sure sign of gum disease. Blood is rich in iron, which is why it leaves behind a metallic taste.

Gum disease can and should be treated to avoid complications such as tooth loss. If you suspect that gum disease may be causing the metallic taste in your mouth, make an appointment with your dentist.

Burning Mouth Syndrome

This fittingly named syndrome causes a burning sensation on the tongue or mucous membranes inside the mouth without a known cause. It is often followed by a bitter or metallic taste. Additional symptoms may include a dry mouth with increased thirst and loss of taste.

Medications used to treat burning mouth syndrome include tricyclic antidepressants, benzodiazepines (often used to treat anxiety), and gabapentin (used to treat pain and seizures).

Mouth Injury or Oral Surgery

Mouth injuries (such as biting your tongue) or oral surgery (such as wisdom teeth removal or a tonsillectomy) can likely lead to a metallic taste in your mouth.

The taste may linger until the bleeding is under control and the wound heals.

Medications

Hundreds of commonly used medications can leave behind a metallic taste because they interact with taste sensations in the brain. Some of the more common medications responsible include:

• Angiotensin-converting-enzyme (ACE) inhibitors, such as lisinopril
• Antibiotics, such as amoxicillin
• Diuretics, such as acetazolamide
• Chemotherapy drugs, such as bleomycin

Chemotherapy and Radiation

A metallic taste in the mouth following chemotherapy or radiation treatments is so common that it is often referred to as "chemo mouth." The effect usually manifests as a metallic taste, but it can also cause the foods you eat to taste like metal. This is referred to as a taste hallucination.

Scientists aren't entirely certain why the taste change occurs after chemotherapy or radiation, but it is widely believed to be caused by damage to cells in the mouth that these treatments cause.

Vitamins and Minerals

Heavy metals found in various vitamins can bring about a metallic taste in the mouth. This includes vitamins with:

• Copper
• Iron
• Zinc
• Chromium
• Iron
• Calcium
• Iodine

Women often experience dysgeusia when taking prenatal vitamins, due to the high levels of iron that these vitamins typically contain.

Additionally, some foods are fortified with vitamins and minerals like iron and zinc that can cause a metallic taste. Commonly fortified foods include:

• Breakfast cereals
• Bread and flour
• Powdered and fluid milk
• Eggs
  
• Iodized salt

Sinus Problems

Conditions such as upper respiratory infections, colds, sinusitis, enlarged turbinates, deviated septum, or even a middle ear infection can cause abnormalities in your sense of smell and, subsequently, your sense of taste.

Allergies (such as tree pollen) can lead to sinus problems and a strange taste in your mouth. Addressing the underlying problem can be the answer.

Pregnancy

Hormonal changes during pregnancy can cause disturbances in taste and smell. These changes may manifest as a metallic taste in your mouth.

Like morning sickness, the unusual taste is often more common in the first trimester than later in pregnancy.

Food Allergies and Anaphylaxis

Specific food allergies, such as to shellfish and tree nuts, have been known to cause a metallic taste in the mouth.

It could also be an early symptom of a serious allergic reaction called anaphylaxis. The metallic taste can begin almost immediately, before other symptoms of anaphylaxis. These symptoms include swelling, itchy skin, difficulty breathing, wheezing, nausea or vomiting, headaches, and disorientation.

Gastrointestinal Issues

Certain gastrointestinal issues can lead to a metallic taste in the mouth, including:

• Gastroparesis (delayed gastric emptying)
• Gastroesophageal reflux disease (GERD)
• Acid reflux

These conditions cause regurgitation of stomach acid into the mouth. Over time, the regurgitation of stomach acid and stomach enzymes can affect how well the taste buds work.

Managing the underlying gastrointestinal issue should help resolve the metallic taste. This will likely involve a combination of eating less fats, decreasing the frequency and size of meals, and prescription or OTC medication.

Exposure to Mercury or Lead

Exposure to certain chemical elements such as mercury or lead can cause a metallic taste in the mouth. You can encounter lead in old building materials such as chipped or flaking paint. It can also be present in contaminated water.

Mercury may be found in contaminated water or in some of the foods you eat, such as fish.

If you think you or your child might have been exposed to mercury or lead, contact your healthcare provider. 

Diabetes and Low Blood Sugar

Diabetes and low blood sugar are both known to cause taste disturbances, including a metallic taste in the mouth. A common diabetes medication, metformin, is also a likely trigger.

Neurological Diseases

Neurological problems, such as Alzheimer's disease or other types of dementia, can cause the brain to misinterpret signals coming from the taste buds. This can result in loss of appetite and a metallic taste in the mouth.

Other neurological problems that can set off this reaction include:

• Bell's palsy
• Brain injury or tumors
• Multiple sclerosis
• Parkinson's disease
• Stroke

Kidney Failure

Another serious cause of a metallic taste in your mouth is kidney failure. Uremic toxicity (excessive uric acid), which is due to a loss of kidney function, can cause taste changes.

Keep in mind that this is one of many possible signs of kidney problems.

Sjogren's syndrome

Sjogren's syndrome is an immune disorder that causes a decrease in the amount of saliva in your mouth. Some people with Sjogren's syndrome report experiencing a metallic taste in the mouth.  

Home Remedies

Treating dysgeusia means treating the underlying condition causing it. With that being said, staying hydrated and preventing dry mouth can help manage dysgeusia in most cases.

If you smoke or use tobacco in any form, it's important to quit. Tobacco contains nicotine, which reduces saliva flow and results in dry mouth.

In addition to drinking plenty of water, other strategies that may help reduce the metallic taste include:

• Rinsing your mouth before and after meals with salt water or water with baking soda
• Marinating meat with lemon juice, vinegar, or other juices to stimulate saliva production
• Chewing sugar-free gum between meals
• Using plastic utensils instead of metal
• Avoiding canned food items

When to See a Healthcare Provider

A brief flash of a metallic taste in your mouth is usually nothing to worry about. In fact, if you've recently started taking a new medication, there's a good chance it's the cause. It should go away as your body adjusts to the medicine.

See your healthcare provider if the sensation persists or you develop other worrisome symptoms.

Summary

Gum disease and poor oral hygiene are two likely reasons why you may be experiencing a metallic taste in your mouth. So are burning mouth syndrome and a mouth injury or recent oral surgery. Medication, vitamins, a food allergy, and sinus problems can also cause the unpleasant sensation.

It's usually nothing to worry about unless the taste persists or you develop other symptoms, like a fever. Then it's time to see your healthcare provider. In the meantime, a few coping tactics can help minimize the taste.