Why Your Breath Smells Like Mothballs (and What to Do)

Bad breath can be frustrating but may also provide clues to your overall health. This is especially true if your breath has a distinctive odor, like mothballs.

A 2018 study found that the enzyme known as tryptophan can lodge and grow between teeth and under gums, and it’s specifically tied to mothball breath.

Tryptophan is used by bacteria in the mouth to produce the molecule skatole, which smells really bad. Skatole gives animal manure its distinctive smell and can make human breath take on the displeasing scent of mothballs.

Tryptophan is also found in mucus. If you produce copious amounts of mucus, there will be more tryptophan for bacteria in your mouth to catalyze into skatole.

Conditions which might cause excess mucus in the mouth include:

• allergies
• postnasal drip
• respiratory infections, such as common colds and the flu
• sinus infection
• asthma
• acid reflux
• lung diseases, such as chronic obstructive pulmonary disease (COPD), chronic bronchitis, and pneumonia

All types of bad breath are generated by bacteria. Bacteria can coat the teeth, tongue, gums, mouth, and throat, feeding off of food particles, enzymes, and other substances.

Bacteria are more likely to thrive and grow when your mouth is dry. Conditions that generate excess mucus in the nasal cavities may cause you to breathe through your mouth, making it dryer than normal.

For that reason, having dry mouth can intensify mothball breath. Many conditions and medications also cause dry mouth. Talk to your doctor about the medications you’re taking and their side effects.

If your breath smells like mothballs, your doctor can help. Treating and managing the underlying cause will help to eliminate or reduce the occurrence of mothball breath.

Based on your condition, you may need over-the-counter (OTC) or prescription medications, such as:

• decongestants
• antihistamines
• antibiotics
• antacids
• corticosteroids
• bronchodilators

Oral hygiene

Tackling the underlying cause, however, won’t be enough to eliminate mothball breath completely. You’ll also need to maintain good oral hygiene habits every day. These include:

• brushing your teeth when you wake up, after meals, and before bed
• using a mouth rinse specifically designed for dry mouth
• flossing teeth
• using a tongue scraper
• drinking lots of water
• avoiding foods that bacteria like to feed on, such as sweets and starchy carbohydrates

Using an electric toothbrush may help rid your mouth of bacteria and excess tryptophan. Home remedies for bad breath, such as chewing parsley, can also help.

Mothball breath is caused by conditions that produce too much mucus in the mouth.

Treating the underlying condition will eliminate the smell of mothball breath.

Maintaining good oral hygiene habits is also necessary for keeping mothball breath — and all types of bad breath — at bay.