Thanks. A vet should be able to find the cause, but they are going to have to run some testing. The clear discharge suggests more of an allergy or viral cause, but you still have to consider a bacterial infection, a nasal tumor, a fungal infection or nasal mites. I will say that with nasal mites, they are usually sneezing a lot, but it doesn't hurt to do empirical treatment for mites. Usually, ivermectin injections will correct that. First and foremost, some blood work and x-rays of the nasal passages need to be done. An x-ray may show a sinus problem, a potential nasal tumor or destruction of the nasal passages. If she had previous problems with an upper respiratory infection, then it can cause some permanent damage to the nasal passages that will lead to chronic sneezing. Sometimes anti-histamines may not completely eliminate an allergy, and it may help to put her on a round of Temaril or prednisolone to further rule out an allergy. This will provide stronger ant-inflammatory and allergy control. Even if the teeth are clean and look good, it still doesn't rule out a potential tooth root abscess. I have seen them with otherwise healthy looking teeth and gums from the mouth. An x-ray should be able to rule that out. In addition to routine blood work, your vet may want to consider checking a blood panel to rule out some fungal infections, especially if they are common in your area. Lastly, if everything looks normal on blood work, or if x-rays show something abnormal, your vet may need to refer her to an internal medicine specialist to get a scope placed into the nose in order to get a good visualization of what is going on. Sometimes that is necessary to get the full diagnosis of nasal problems. If there is concern about a viral infection, anti-viral medication can also be prescribed. I just wouldn't expect a viral infection to last for 3 months. If blood work is normal, though, I would consider trying her on a steroid, like prednisolone or Temaril first to see if that help. Please let me know if you have any other questions or concerns. Hope this helps.
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