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Licking the mouth usually indicates excessive salivation and is usually a sign of mouth pain, nausea or sometimes a seizure. Check your dog’s mouth for tartar on the teeth, possibly red gums, darkened teeth, broken teeth or something caught between the teeth or gums. If you find something stuck, try and remove it. If it is bad teeth, you can give him Buffered aspirin can be given to a dog with a dosage of up to 5 mg per pound every 12 hours. Keep in mind that a dog's body does not metabolize aspirin in the same way as a human and thus should not be given more than a day or two without contacting your Vet. The aspirin may need to clear your dog’s system before other medications can be given, so keep that in mind if you decide to give aspirin and be sure and tell your vet when your dog is seen.
You should also check just under your dog’s jawbone for a swelling and under your dog’s tongue for a swelling. This is where some of your dog’s salivary glands are located. If you find a swelling here, it’s possible your dog has an accumulation of fluid near the salivary gland called a sialocele which is causing your dog to salivate more. This condition does require your dog to be seen as soon as possible. You can read about it here:
If you suspect it may be due to nausea which is a likely cause, you can try some Pepto-Bismol which can be given to a dog at 1 tsp per 5 pounds every 6 hours for upset stomach, gas, or diarrhea.
If she becomes uncomfortable, you should take her into the vet. If it is possible that your dog ate something toxic such as chocolate, cocoa mulch, antifreeze, medications they will need to see a vet immediately.
You can read more about excessive salivation on the following website:
Now some dogs can have an allergic reaction to various things such as new treats, plastic, etc which can cause redness around the mouth and itchiness and even nausea. This can also lead to drooling due to the nausea which can lead to a skin dermatitis around the mouth area which becomes itchy. This can lead to more lip licking and even to a dog rubbing their face on everything. This is often described as a lip fold dermatitis. You will want to keep the area clean and dry. Benzoyl Peroxide wipes are also effective for cleaning the folds as well and to keep bacteria in the area down. It can be challenging to keep it dry but will help if you can keep it dry.
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