Understanding cat sleep cycles

Hi everyone. I am looking for some general info on what is considered a typical sleep pattern for cats. I have two cats, Holly who is an 8 year old calico and Ivy who is 4 and black. Holly has been on thyroid meds for a while now. Lately she seems to be napping way more during the day than she used to. Is this just part of getting older or should I be worried? I know we talked about her twitches in another thread but the amount of time she is just lying down is making me anxious.

Hi Sharon. First off, don't panic. Cats are polyphasic sleepers, meaning they sleep in short bursts throughout the day. For a senior cat like Holly, sleeping 16 to 20 hours a day is actually quite standard. As they age, their energy levels drop and their bodies need more rest to repair themselves. I wrote up a breakdown of REM vs non-REM sleep in Cat sleep cycles explained if you want the technical details, but the short version is that if she is eating and using the litter box normally, the extra naps are likely just age-related.

That helps to know, thank you Tom. I will check out that thread. I have been watching her closely because of the thyroid stuff. I recall reading somewhere that the meds might make them drowsy. Is that a thing or am I mixing up facts?

I think you might be right about the meds. I have a 7 year old calico named Whiskers who is dealing with arthritis. Her vet mentioned that some medications can affect their activity levels. We did a lot of research on this. I wrote a thread about Managing arthritis in sleep where I detail how we adjusted her environment, but I also note that her sleep duration increased when we started certain supplements. It is worth checking if her thyroid levels are stable. If her T4 is too high, she might be sedated.

I have a 5 year old dsh named Bean who is very shy. I noticed that when she is stressed, she sleeps a lot more. It is like she is shutting down to cope. So sometimes the sleep increase is behavioral rather than medical. Did Holly have any changes in her routine recently? New pets, new people, or even a change in where her bed is?

Good point Abel. Nothing major changed, but I did move her food bowl a few feet away to make room for my new bookshelf. I didn't think that would matter. I am going to move it back tonight and see if that helps. I am also going to look at the thread about Twitching during sleep in seniors again because I want to make sure the twitches aren't related to the sleepiness.

The food bowl location probably isn't the cause of the sleep increase, but it is good to be consistent. Regarding the twitches, if they are small muscle movements, they are usually just REM leakage and are normal. However, if she is having seizures or not waking up when you call her, that is different. I have a thread coming up soon about When sleep changes are dangerous that covers the red flags. For now, if she is responsive and eating, keep an eye on her. If you are still worried, call your vet for a quick check-in. Better safe than sorry.

I agree with Tom. Also, since you asked about the thyroid meds, I found a very detailed write-up on how they affect sleep patterns in Thyroid treatment and sleep. It lists the specific side effects we saw in our clinic data. It might give you more peace of mind or tell you exactly what to look for at her next appointment.