Re: passed a roundworm. Took course of vermox. Not passed any more roundworms.

You wrote:
"I dont understand what you said about them passing through partly digested if they die abruptly. Surely they would not be able to exist in the intestines if it was possible to digest them at all :/ Do you mean they might have been passed without being easily visible if there was not a large number?"

Once they die, Tapeworms and roundworms lose the ability to resist the digestive enzymes. So how intact they are when expelled partly depends on where they were in the digestive tract and how quickly they are killed. The following web page discusses this with regard to tapeworm, for example (see Action section): http://www.drugs.com/vet/drontal-plus-small-dogs-can.html

Also, persons infected with one type of parasite are often infected with another. That's another reason why taking more than one medication to cover both roundworms and flatworms might be considered. Tweet