I have same issue been dealing with it for 18 years now. I went to over 10 doctors and dentist. But unlike some ppl hear. mines smell all the time but if I eat certain foods like McDonald’s or candy or alcohol, the smell can fill up a room. My family won’t even drive in the same car as me. I’ve done all the antibiotics nothing works. I do have post nasal drip sometimes and I recently coughed up a tonsil stone but I never seen one before and I don’t see anymore but the bad breath remains. I just went to a doctor who said if the smell persists after 2 months of antibiotic treatment that I should get my tonsil removed