Thanks for the information. No wonder I couldn't find it! Thought my google skills were going soft on me.
This medication is 250mg Cephalexin. This medication is commonly used for skin issues in dogs and not usually used for infections in the mouth. The dosage used for this usage is typically 1 capsule twice daily for 7-14 days.
It's most likely that Jitterbug does not have a random infection but probably has some dental disease and associated inflammation of the gingiva. This often causes sensitivity and bleeding. Additionally, the aspirin you're giving can exacerbate bleeding as it has anticoagulant properties. It's possible the appearance of her symptoms look worse than they are with the medication she's being given.
If she does have dental disease present, the best thing to do is to have a physical exam performed by a veterinarian and to schedule a dental cleaning. This is performed while the dog is completely sedated and the calculus is scaled by hand by the veterinarian or qualified technician. Depending on how bad the disease is, your vet may wish to place her on antibiotics before and/or after her dental to prevent further problems (medications like Clindamycin are typically used for oral concerns). Once this is done, the gingiva will go back to being pink and healthy and won't bleed. You'll still need to keep up with brushing her teeth, but it's very common for small breeds like rat terriers to need dentals every 1-3 years even with regular brushing of their teeth.
Two things that you can do to prevent buildup are to give hard chew toys like nylabones and knuckle bones that will help to scale calculus as she chews. Additionally, there are products that can help alter the flora within the mouth and prevent calculus from forming as quickly. As hesitant as I was to believe a product like this would work, I have seen some astounding benefits from it within the clients that are using it on their small dogs. Fellow technicians who are using it also rave about the benefits they see in their own dogs (and cats). What's more, it can be added to water to form a paste and used as a tooth paste which shows even more benefits because of its direct use: http://www.wysong.net/products/dentatreat-dog-cat-supplement.php
More information on canine periodontal disease: http://www.avdc.org/periodontaldisease.html
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