My dog's breath suddenly smells bad. Is Doxycycline causing it?

Lily could have dental disease causing foul breath - bacteria form plaque on the teeth and underneath the gumline and cause bad breath. She could have a mass or wound in her mouth if this is a sudden change, or occasionally dogs with gastrointestinal disease will also have bad breath. I'd recommend having your veterinanrian examin Lily's mouth -she may need a dental exam and cleaning under anesthesia.

It's odd that it improved when the [Giardia](https://www.petcoach.co/dog/condition/giardia/) was treated. My first suspicion for the ongoing odor is that she may be licking at her anal glands or eating her own (or someone else's) poop. Ideally, have her examined by a veterinarian just to make sure there are no wounds, irritation, etc in her mouth or throat that maybe contributing. You r vet can also check her anal glands to see if they seem full or irritated which could lead t her having a tendency to lick at them a lot. If her anal glands are fine, and her mouth is fine, use a daily product for dental health. [CET products](https://us.virbac.com/cet-veggiedent-fr3sh-dental-chew-for-dogs) contain chlorhexadine which kills bad breath causing bacteria. [Water additives](https://www.petco.com/shop/en/petcostore/product/zymox-oratene-water-additive) are great too. I hope thats helpful for you. Thanks for asking PetCoach! Good luck!

It would be best to have a veterinarian do an exam on him. It’s possible he may have a wound on the roof of his mouth or back of his throat, or a piece of grass or a small twig stuck on a back tooth, etc, or a wound elsewhere in his mouth. It’s also possible that he’s having some tooth root problems with the recent eruption of adult teeth. If he is eating fine and otherwise acting normally, it’s ok to try brushing his teeth and try a rinse or water additive designed for halitosis (bad breath) in dogs. However if that doesn’t help after a few days, I would strongly recommend that you take him in. Thanks for asking Petco Pet Education Center, formerly Petcoach!

Missy appears to have several areas of bone loss and exposed tooth roots. I suspect she has several diseased teeth and significant infection. Sometimes severe bone loss can results in deep ulcers and even fistulas. I recommend to discuss having Missy sedated to remove the diseased teeth and clean out any ulcers. Then give her mouth time to heal. It’s unlikely that this problem and the odor will go away with out the full treatment. Ulcer and bad teeth can cause discomfort. Not to mention if can lead to other diseases as well. I hope this helps and please feel free to post any additional questions.

You may want to have Rudy Sue examined by your vet - sometimes food or debris can accumulate near an extraction site or the sutures can break down. It’s also possible hat the bad breath is not a dental problem - dogs with chronic gastrointestinal issues can have halitosis. I have never heard reports of lung cancer causing halitosis and I think this would be much less likely.

Dogs with bad breath usually have terrible teeth...ie their teeth are full of tartar which harbors gas producing bacteria and that stinks. These bacteria also cause severe gingivitis (inflamed gums) which allows the bacteria to enter the blood stream and eventually cause heart and kidney problems. Another reason for bad breath could be a tooth root abscess, a wound in the oral cavity and renal failure. Please take Voodoo to a veterinarian for an exam to find the cause of the bad breath. Treatment can then be initiated, ie a dental cleaning, antibiotics to kill those bacteria and/or early detection of renal failure.

Halitosis is the word we use for bad breath. It is most commonly caused by dental disease. I am attaching a handout below with more information on halitosis. http://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=129 Since Luckyboy appears to have some pain in his mouth, I would definitely recommend having him evaluated by your veterinarian. In order to determine the severity of his dental disease, they will need to perform a dental under anesthesia so they can fully evaluate each tooth under the gumline. If they find a broken, painful or infected tooth, they will be able to remove that tooth and resolve Luckyboy's pain. I am attaching a handout below that discusses periodontal disease. http://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=222 Good luck! I hope that was helpful and that Luckyboy will feel better soon. Thanks for using PetCoach.