My indoor cat threw up a worm after deworming. Should I re-deworm?

I’m going to guess that this is a roundworm. It can be difficult to identify adult worms but it is usually much easier to identify eggs in a stool sample. I would recommend seeing your veterinarian for a stool analysis and to get the appropriate deworming medication.

Poor kitty. Typically most pets require a second deworming 2 weeks after the 1st to treat for re-emergence of worms because of their life cycle, so yes it is appropriate to deworm Molly at this time. Pyrantel palmoate or Fenbendazole are typicallly used. This should clear things up for good, as long as she doesn't get re-infected from exposure to the outside. Keeping her on a monthly flea preventative like Revolution can also help prevent re-infection because it contains an intestinal dewormer in it as well.

That looks like a roundworm. You need to deworm a cat every two weeks when they have worms due to the life cycle of the worm. The deworming treatment will not kill eggs. So the first treatment kills the adult worms present while the second one kills the worms that had not yet hatched at the time of the first deworming. Give Max a deworming treatment now, another in two weeks, and then another two weeks after that to be safe.

Sometimes the worms die and just come out like mucus in the stool, not full worms. If you gave the proper dose I’m sure it was effective. You can repeat the deworming in two to three weeks to be sure and follow the directions on the package. Thanks for using Petco Pet Education Center, formerly Petcoach to help you care for your cat.

It could be they had worms previously and you didn't know it. It sometimes can take until there is a heavy infestation of worms for you to see them in vomit or feces. Typically only eggs are passed in the feces, and those eggs can be seen with a microscope, not the naked eye. You have to repeat the deworming treatment to kill all the worms. The first one treats the adults already present, while the second in two weeks will kill the ones that had not yet hatched at the time of the first treatment. Hopefully you will stop seeing dead worms in the next couple of days, but it means the treatment is working. Best of luck.

I would recommend letting your veterinarian know that Bernie vomited a roundworm. It is very common for puppies to have roundworms and the dewormer is most likely killing them off. I would recommend depending on what type of dewormer to deworm again in 2 weeks or change the dewormer. Sometimes it takes a second round of deworming puppies. Thank you for using Petco Pet Education Center, formerly Petcoach.

Deworming doesn't directly stop vomiting. IF the vomiting is indeed caused by the intestinal worms, I would expect vomiting to stop within a week or so of deworming, but it could be longer if the parasite load was causing a lot of irritation. I would still recommend a recheck if still vomiting after 5-7 days.