Hi there,Thank you for your patience. As you can probably appreciate, there are a large number of possible causes for Buster's symptoms this evening. The combination of lethargy and being off his food could potentially be associated to an early gastroenteritis, gastrointestinal worms, a toxicity, or even just a behavioral issue (to name just a few potential causes). Because there are so many potential causes for his symptoms, you will need to continue to keep an eye
on your boy for now. In particular, please keep a close eye on his mucus membranes, capillary refill time and respiratory rate as follows:Mucus membranes - flip his lip and look at the color of his gums. They should maintain a nice salmon pink color. Get him to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.Capillary Refill time - this measures blood perfusion and test this by putting your thumb on his gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.Respiratory Rate - if he is continuously panting throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.If he seems really lethargic, or if he won't drink anything at all, then you are best to play
it safe and have him seen tonight if you can. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!Kind Regards,Dr EPS: If you have additional questions after you rate the question, you are welcome to request me for additional conversations if I am on-line or by beginning your question "Dr. E..." or "Pet-doc..." and others will leave the questions for me.