Why Do I Have a Bad Taste in My Mouth?

Your coffee tastes like a coin. Your toast tastes like a coin. You’ve brushed twice, rinsed, chewed a mint, and the taste is still there, sitting at the back of your mouth like a tenant who won’t leave.

What it is

Cleveland Clinic² calls it dysgeusia, a disorder that distorts your sense of taste. People describe foods tasting metallic or bitter, losing their sweetness or saltiness, or tasting rotten. Some notice an unpleasant taste even when they haven’t eaten. Treatment, Cleveland Clinic says, depends on why you have it.

The causes, from common to less common

Not enough fluid, or a dry mouth. Cleveland Clinic³ says dehydration is one of the most common reasons for a bad taste, and that dry mouth, from less saliva, impairs taste. Our article on waking up with a dry mouth covers that.

Acid reflux. Cleveland Clinic² says that when stomach acid enters your mouth it can affect your taste, and that chronic heartburn may mean GERD. See heartburn and GERD.

Medicines. Cleveland Clinic³ says many medicines affect taste, including allergy drugs and antibiotics, and names clarithromycin, metronidazole, blood pressure drugs, lithium and diabetes medicines in its metallic-taste guide. Harvard Health⁴ explains one route: antidepressants, antihistamines and opioids reduce saliva, which intensifies metallic flavors, and metformin is excreted through the salivary glands.

Vitamins and supplements. Cleveland Clinic³ says multivitamins with metals such as zinc, copper and chromium, iron supplements and prenatal vitamins may trigger a metallic taste.

Mouth health. Cleveland Clinic³ lists poor oral hygiene leading to gingivitis or a tooth infection, and says the metallic taste typically goes away after the infection is gone. It also lists severe tooth decay, abscesses and oral thrush. If your tongue looks coated, see a white tongue.

Colds, sinus problems and infections. Cleveland Clinic³ lists colds, sinusitis, upper respiratory infections and COVID-19, and says a COVID-related metallic taste can last for weeks or months. Kidney infections and hepatitis are also on its list of infections.

Hormones. Cleveland Clinic² says dysgeusia in pregnancy is common, usually from a surge of hormones. Cleveland Clinic says it’s at its worst in the first trimester. Cleveland Clinic also says menopause can change taste sensitivity.

Smoking and aging. Both are on Cleveland Clinic’s³ list.

Other conditions. Cleveland Clinic² names zinc and vitamin B deficiencies, diabetes, thyroid disease, kidney and liver disease, nerve damage, and neurological conditions. Harvard Health⁴ lists diabetes, heartburn, kidney or liver problems and zinc deficiency.

What helps

Fluids. Harvard Health⁴ says to increase your fluids, from drinks or watery foods like soup and fruit, to dilute unpleasant tastes.

A rinse. Harvard Health⁴ suggests rinsing your mouth with water and a dash of salt or baking soda before you eat. Cleveland Clinic¹ also lists a baking soda rinse.

Saliva helpers. Cleveland Clinic¹ lists sugar-free gum and ice chips to activate the salivary glands.

Brush, floss and scrape. Both sources say oral hygiene helps, and Harvard Health⁴ says to use a tongue scraper twice a day.

Change the menu. Cleveland Clinic³ suggests glass or plastic utensils instead of metal, and Harvard Health⁴ suggests chilled or room-temperature foods, citrus or naturally sweet foods, and skipping red meat, which it says is high in iron and zinc.

Quit smoking. Cleveland Clinic² lists it.

Cleveland Clinic³ adds an important caution: see a doctor to find the cause rather than masking the symptom.

The play

Try this: a taste log and a rinse

For a week, write down when the taste is worst: after a new medicine or supplement, first thing in the morning, after meals, or with heartburn.

Add a salt or baking-soda rinse before meals, plus water and sugar-free gum between them.

If one pattern stands out, you have something specific to tell your clinician.

When to get checked

Cleveland Clinic¹ says to see a provider if the taste lasts beyond one week or gets worse, and sooner if you also have symptoms beyond your mouth, like unexplained weight loss, fatigue or feeling ill. Harvard Health⁴ says that if you notice a persistent metallic taste, report it to your doctor, especially to explore changing a medicine if one is the cause.

Book an appointment if any of these fit:

• The taste has lasted more than a week
• It started after a new medicine or supplement
• You have tooth pain, swelling or a sore that doesn’t heal
• You’ve lost weight without trying, or you feel unusually tired or unwell
• You have regular heartburn
• You’re pregnant and it’s affecting your eating

The tenant can be evicted. First, find out whose lease it is.