Help Hamster making loud noise in his sleep

[Margrethe]

Hello hamster lovers

I could use a little help.

How often:
Yesterday my hamster started making loud noises in his sleep, waking himself up. It is very sudden and is unfortunately still happening. He runs in his wheel all the time, but yesterday night he didn't come out at all. During the night he stayed in his house and kept making loud noises. I don't know the intervals since I was trying to sleep myself, but I did check on him once during the night because of how loud it was. He seemed just fine (and confused when I lifted his house). However he is still making noises and has been all day long. It is now 8pm. I am very worried. It is now happening every 10 minutes and everytime it happens he wakes up. (I can see movement from the bedding and occationally a cute nose). He is not sleeping well.

The sound:
Here is a link to a youtube video I found in which a hamster is making a similar noise:
https://www.youtube.com/watch?v=aV29...wVaqsygWdXLGsg
He only makes the noise once and then immediately wakes up and tries to go back to sleep.

[cypher]

It's hard to say what it might be, if it's hot where you are it could be related to that, hows the ventilation in his house, is it plastic? Have you changed substrate or anything in the cage?
If it continues I would get him checked by your vet in case he has a respiratory infection.

[Margrethe]

He doesn't seem to be too hot. He's not sleeping "outside" any of his hideaways, not drinking more than usual and his fur isn't "wet".

His house is made of wood. I removed it from his cage and gave him some more nesting material to see if that had any effect, and then sat next to his cage for hours to observe. It helped a lot. Already after 15 minutes he had calmed down tremendously.

The ventilation in his cage is good, and I didn't change up any bedding/substrate.

Today though I noticed him making the sound while he sat on my lap. He was sort of in his hamster-freeze-state, where he just sits still, stares and is completely blank. I don't know if all hamsters do this, but I've had many that have. Anyways, it kind of jerked him out of it and it almost sounded like a cough? I'll just note that I he is a syrian hamster, if that makes any difference.