Bad breath can arise from a problem in your mouth or throat, or from metabolic processes. Depending on the cause, your breath may smell sweet, sour, rotten, musty, fishy, or like ammonia.

A person’s breath may smell like urine or ammonia due to numerous causes, including nasal congestion, stomach infection, and diet. A foul taste in the mouth may indicate bad breath. Read on to ...

Bad breath happens to us all, but sometimes it’s the sign of a serious illness. If your breath smells like acetone -- the same scent as nail polish remover -- it could be a complication of ...

If the breath of a person with diabetes smells like acetone, this could indicate diabetic ketoacidosis. Learn about the connection between diabetes and acetone-like breath.