How long does dewormer take to cause diarrhea in a cat?

Question

We gave our domestic short hair cat (a neutered male rescue cat) an off the shelf dewormer tablet from a petstore the active ingredients were "Pyrantel embonate 230mg, praziquantel 20mg." Both of those ingredients can cause diarrhea

36 hours later he now has diarrhea, not bloody, but serious enough for him to foul himself in his sleep. He may also have taken a rat last night.

We are wondering is this just the dewormer working or should we be concerned about another cause? Is 36 hours too long for this to be linked?

Answer 1

If the diarrhea is still going on when you read this, you need to get your cat to the vet right now. It takes a very short time before cats get dehydrated.

Some cats get diarrhea after getting dewormed, but it is not a very common side effect for cats; the next time you deworm your cat, you might try another brand.

When a cat gets diarrhea from deworming it will often get better in less than 6 hours. If it lasts longer you need to get your cat to the vet.

Do not feed dry food to your cat if it has diarrhea; it will make the cat more dehydrated. Feed only wet food and water until your cat gets back to normal.