I am sorry Charlie is not feeling well, I am sure this must be a little stressful for you. In response to your question, the green color discharge is consistent with an infection in the eye. Flushing the eye with sterile water is a great idea, I would encourage you to continue doing this, but, Charlie should be seen by your family veterinarian for prescription topical antibiotics. My other concern is the weight loss and that he may be drinking more than usual. You see, these symptoms could be related to kidney disease, hormonal disorders (diabetes, hyperthyroidism), and even cancer to name a few causes. It is important that he has a blood test done to rule out most of the above-mentioned diseases. Unfortunately, we are very limited as to what you can do at home without knowing exactly what is wrong with Charlie. For example, if he is hyperthyroid he will be placed on medication to help lower the thyroid levels. In turn, this will help him gain weight. So, treatment for Charlie will be based on exam and test results.
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