What causes bad breath even after brushing?

It is not uncommon for people to experience halitosis, but most people find that it improves after a thorough brushing.  In some cases, even after brushing, flossing, and using mouthwash the bad breath persists and can even indicate more serious health issues.

Possible causes

• Poor Oral Hygiene – If you have gum disease or untreated cavities affecting your mouth, the bacteria will endure the at home remedies.  A professional dental cleaning or even dental treatments can remove the bacteria from the cavity or from pockets in the gum.  Once the bacterial growth has been addressed, the bad breath caused from the infection and inflammation should improve as well.
• GERD – Gastroesophageal reflux disease is a chronic condition caused by acid from the stomach moving up the esophagus.  The pH level of the strong stomach acids meant to digest your food are problematic when they are outside of the stomach.  If your bad breath is from GERD, then you may find relief from over the counter or prescription medications.  Those medications can include antacids, proton pump inhibitors, or ones to help keep the muscle from your esophagus to your stomach closed.  You can even adjust your diet to decrease inflammatory foods and talk to your doctor about surgical options if you are not finding any relief with other treatments.
• Vomiting – If you have experienced food poisoning or a viral infection, the cause of your vomiting will need to pass out of your system.  After the vomiting subsides and your health starts to improve, your bad breath should improve as well.  If your vomiting is severe and persistent, the doctor may want to use an anti-nausea medication or even IV fluids to treat the dehydration that can worsen your bed breath.
• Sinus Infections – If your sinus cavities are infected and draining in throat, the bacteria ridden mucus will most certainly cause bad breath as well as discomfort.  After a course of antibiotics and over the counter anti-inflammatory medication, your infection should improve and this cause for your bad breath should also clear up.
• Ketoacidosis – Based on some popular diet trends, this may sound like a condition that indicates weight loss, but it is an indication of imbalanced blood sugar and insulin levels or serious infections.  Only a doctor can diagnose you with diabetes or adjust your diabetic medication, so if you believe that your bad breath is pointing to a larger issue, make an appointment with a doctor.
• Liver Failure – If you have already been diagnosed with liver problems, your bad breath can point to liver failure.  Issues like cirrhosis, poisoning, or hepatitis will need medications prescribed by a doctor.  If your liver is no longer able to be restored, then the doctor may need to talk to you about a liver transplant or the more pressing conditions causing the liver failure like obesity or alcohol dependence.
• Bowel Obstruction – If you believe your bad breath is an indication of bowel obstruction, it is imperative to not waste time in seeking medical attention.  Emergency medical treatment can include IV fluids, surgery, or medication and after your bowels are restored to health, your breath should improve as well.

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