Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
This poor guy. Unfortunately, his symptoms are vague (coughinging/possibly gagging and lethargy) and could indicate one of a long list of potential problems ranging from ingestion of an unusual item that is irritating the digestive tract to infection (bacterial, fungal, viral such as feline leukemia virus, parasitic) to organ problem (liver, kidney) to pancreatitis and the list continues. I so much wish I could narrow this down for you and provide a diagnosis, but I cannot. To do so would require an examination followed by some testing that might include lab work (CBC, chemistry panel, urinalysis, stool check) +/- radiographs (X-rays).
If he was eating normally and not having any true vomit/diarrhea then you could monitor him, but the lethargy worries me he may be running a fever, experiencing pain or otherwise feeling quite ill. This symptom is the one that indicates to me he really needs to be seen by his veterinarian today.
I am at a point I need to know what questions you have. I hope that the information I provided has been helpful.
Please let me know if for any reason you need further clarification, have more questions, or were expecting a different type of answer.
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