Vomiting worms after deworming

[KevinTheBird]

I dewormed my cat yesterday. I normally do it every couple of months but due to lockdown and everything I just forgot and it’s been nearly 4 months since I last did it.

He’s normally a bit tired and off his food for about 24 hours after worming which he was all of yesterday afternoon. I woke in the night to the sound of him vomiting and the vomit had several worms in (roundworms, I think, having looked online).

I can’t work out if this means the treatment was successful though. All the information I can find just says worms in vomit is a clear sign that they have worms. I don’t know if I need to treat him again - in which case I guess I’d have to take him to the vets as the worker says don’t use more than once every 6 weeks. My vet is only offering emergency appointments at the moment and my insurance has a £75 excess so ideally I’d like to avoid that.

Anyone got any experience with this?

Were the worms alive or dead? If they were dead then it sounds like the treatment worked and his body was just getting rid of them. If they were still alive then it might be worth ringing the vet to ask whether any further treatment is needed. They should be able to advise over the phone without an appointment.

They weren’t wriggling but I didn’t give them a particularly close examination.

Grim. They normally shit them out. I think the treatment will have worked, but certainly ask your vet to be sure.

This is my day job.

Worm him again in about six weeks. If he has them in his stomach he has a high worm burden. They will be roundworms and the wormer has worked. The sudden dead protein in his stomach acts as a toxin and he has hurled them up to get rid. Don't be alarmed. Cats and dogs have a much more efficient puke reflex than we do and it's not as traumatic for them to bring stuff up.

Sometimes when they have a high worm burden they poop worms too.