Cutting off food before vet visit

I need to bring Albus into the vet on Saturday.  He's been having sneezing fits off and on for a few months.  He had his regular exam in April or May and, of course, wasn't having any issues at that time, so the vet didn't really get to see his symptoms.  He's currently in another round of sneezing, and I just want to get it taken care of.  Sometimes his eyes are runny, once in a great while his nose is runny, but both are only coming out clear- no yellow or green.

Anyway, when he went in a couple months ago, he pooped in his carrier both on the way to the vet and on the way home.  It was traumatic for both of us, and I'd like to prevent it from happening again.  His appointment is this Saturday at 1:30pm, so I was thinking of not giving him any food after a certain time so that, hopefully, his system is empty before we leave the house.

Any idea how long a "cycle" takes on a cat?  Midnight the night before?  8:00pm?  

12 hours is what an animal should fast for surgery, sounds like allergies to me tho, it's also actually a good idea if your cat likes treats to with hold food so that you can give it treats while you are there or ask the vet if they have feliway towels or wipes, it has smells that make cats more comfortable at the vet.

You can look online for feliway stuff too on amazon, it's great for cats with anxiety

I'd say 12 hours is about right. Do bear in mind that its amazing how animals can squeeze out a poop when highly stressed/scared - its part of the fight or flight reaction. It might be an idea to get some puppy training pads to line his carrier with just in case (and don't forget spares for the journey home).

Bach's Rescue Remedy might help him be less stressed about the whole thing. Feliway's a great idea too - but do test his reaction to it beforehand. Occasionally, cats really take against the spray version, so better to find out BEFORE you're en route to the vet!

Stay as calm as you can yourself - cats are wonderful at picking up our emotions, so he needs you to be calm for him.

Hope it goes ok at the vet 

Thanks everybody!  This last time was the first time he'd ever done that, and we've had him 7 years.  And Luna did it, too- that's what's extra weird.  

I will try the Rescue Remedy- I've used it before (for other reasons than car rides) and it does help.  We tried Feliway when we moved- got one of the diffusers, followed all the directions.  I don't remember what Luna's reaction to it was, but Albus had a BAD reaction.  It was like he was having a bad drug trip or something!  He was all agitated, making noises he's never made before, getting aggressive with Luna, which he never does.  Within 30 minutes of unplugging it...back to normal.

The only reason I'm a little more concerned about this sneezing is because sometimes it sounds like he's swallowing more than normal, and sometimes, especially when he purrs, there's sort of an extra "gurgly" sound in his throat, like there's a lot of phlegm in there that's getting vibrated, too.  He breathing sounds fine the rest of the time and he's not lethargic or anything.  Even if it is allergies, I just want a doctor to tell me what to do next (if anything).

Good luck at the vets. I hope this trip is less traumatic than the last one!