Brief Answer: Please, see a dentist. Detailed Answer: Hi and thank you so much for this query. I am so sorry to hear about these ulcers you have in your mouth and the bad breathe that makes you feel so uncomfortable. From all the information you have provided, there is an active infection going on in your mouth. This causes a purulent collection and secretion which causes this bad odor. I strongly recommend that you meet and get evaluated by a dentist. The treatment would consist in examining the infection and making the decision to either drain it through minor surgery and or antibiotics that would clear off this infection, treat the ulcer and restore your fresh breathe. Listerine would not be able too clear up this infection all by itself. Though it can kill a good number of germs, it doesn't penetrate deep to all the areas to be able to guarantee complete sterilization that would lead to healing. Also, I will encourage you to avoid consuming sugar containing foods, brush regularly at least morning and evening, continue listerine and pain medications like Tylenol and Ibuprofen while you gain sometime to meet with your dentist. I hope this addresses your query fully. Thank you so much for using our services and please feel free to ask for clarifications if need be. I wish you the best of health. Dr. Ditah, MD.

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