Thank you for your patience. Cinco's symptoms over the last 12 hours are definitely quite concerning and there are a number of possible causes for his lethargy, funny walking and vomiting. Potential causes here include anything from an acute gastroenteritis, to a toxicity or poisoning (hopefully there isn't anything around your home or yard he could have gotten into), to an internal organ issue or even an endocrine problem (to name a few possible causes here). You are going to need to continue to keep a very close eye on your boy, and there is every chance you may need to get him down to your local ER vet today.
One of the primary concerns here is whether your boy is becoming dehydrated. If he isn't drinking much, or is throwing up water when he tries to - there is no doubt that he will be relatively dehydrated by now. This is enough of a reason for you to see your local ER vet today. Here they can start rehydrating him by placing an intravenous line and starting appropriate fluids. For now, you are best to with hold his food until later on this evening, and continue to try and encourage him to drink now by having several bowls of fresh, cold water available for him. Hopefully you have seen him go to the toilet without issue. Male cats can develop a blocked bladder that can lead on to symptoms like this, but you would also notice him straining to pee, and potentially not passing any urine at all. If this is the case, this is a medical emergency - so do get him seen straight away if he seems to be having difficulty here.
For now, please keep an eye your boy's mucus membranes, capillary refill time and respiratory rate tonight as follows (do be careful that your boy doesn't try to bite you):
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 or open mouth breathing at all tonight, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
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