Bad breath can originate from causes outside the mouth:

a) Bad breath from the nose and tonsils and airway:

This can be a cause of bad breath due to bacterial infection. Tonsil stones and infected tonsils can cause bad breath due to the presence of bacteria that release volatile sulfur compounds. Disease of the lungs can also cause bad mouth odor.

B) Bad breath from the intestines:

The gastrointestinal tract is the main cause of bad breath that originates from outside the mouth. Acid reflux, stomach ulcers, obstruction in the intestinal tract and stomach cancer can also cause bad breath.

c) Bad breath due to whole body (metabolic) conditions:

High fever, diabetes, leukaemia, kidney, and liver diseases can cause a bad mouth odor.

D) Bad breath due to medicines (drugs):

Some medicines such as disulfiram, antihistamines, and amphetamines can cause a bad mouth odor.

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