can cats vomit out a tapeworm?

Last week I found worms crawling around in the litter box. I did some Google Research and found they were tapeworms. So I went to the pet store and picked up an all natural dewormer called wrm clear. Youre supposed to give the cat the medicine 3x a day for 14 days. About an hour or two after I gave my cat the first dose, he violently threw up 4 chunks. I had also gave him a new food at the same time as the medicine so I assumed he was just not used to the food and that's why he got sick.
Since then I haven't seen any worms in the litter box so Im wondering if he could have vomited the worm up??

If the med is to be given 3x a day for 2 weeks, then it is likely not strong enough to cause the cat to vomit it up after the first dose.

Likely the food.

The ONLY tapeworm med that works that you can buy in a pet store is called Tape Worm Tabs, sold at Petco stores.

Otherwise you would want to get drontal from the vet, given 1 time, then 1 time in 2 weeks.

Sure is easier then the med you are giving now.

You won't see worm segments all the time in litterbox either, they are only seen when they are shedding.

Be careful about those too, they are filled with eggs, but do dry up after 15 minutes.

You really need to get to the vet and get something to treat the tapeworms.