Can anyone explain these symptoms?

[cuteglasses]

Picked up Salem two weeks ago from a reputable rescue. He's 11. He's settled in really well, eating and drinking well, sociable etc.
This morning in his bed he's had an attack of a mixture of a gagging/coughing for about 30 seconds. No furball, no vomiting.
I've booked a vet appointment for this afternoon.
Any ideas what it might be?

Magic does this. I thought feline asthma but the vet said it wasn't. I suspect she's trying to bring up a hair ball, but swallows it back down.

Piece of grass stuck in throat, asthma, flu - there are quite a few possibly causes. Though piece of grass stuck in the throat is the number one cause.

Boycat does that occasionally, and within a couple of days presents me with a fur ball - or more commonly, liquid containing a few hairs.

However you are right to get the vet to check, as there are plenty of other potential causes.