gagging cat

Question
Hello,
My male 3 year old cat, Charlie, has been acting strange for a few days. He seems very lethargic and is gagging a lot as if he is about to be sick, but nothing passes. He also has not used his litter tray in over a day. He ate about a pouch of food last night, but that is all since Friday (It is now Sunday). At first we thought it might be a hairball and waited for it to pass, but we are now getting a little worried as his behavior hasn't changed at all since yesterday. He is usually a very lively, boisterous cat but at the minute he will let you touch him anywhere without kicking or playing.
Should I see if this passes in a day or so, or should I take him to the vet?

Answer
Hi Sam,

I would get him to the vet at this point.  It's possible that he's not used the litter tray because he's not eating enough to pass anything, but I also worry that he may have an obstruction or severe constipation that could be the cause of his symptoms.  That can be deadly in a matter of a day or so once symptoms like nausea and lethargy begin to arise, so I would feel better to have him checked out right away.  There are certainly other possibilities, like a stomach bug, which the vet will be able to help you out with, as well.  I'm sure Charlie could use an anti-nausea medication and perhaps a gastrointestinal antibiotic/anti-inflammatory, and maybe even some fluids under the skin to combat dehydration since he's been so under the weather.

Best of luck!

Jessica