How fast will the pill my vet gave us work?

Some how my dog got a tapeworm. We are going in the morning to get her the pill. But how fast will it work and what should I know about it. (Like will it make my dog go poo more.)

Dogs get tapeworms from fleas. The vet may give your dog an injection instead of a pill. It will work within 24 hours. Your dog can easily re-infect itself by swallowing fleas. Modern wormers don't make dogs squirt out huge amounts of diarrhea as the old time drugs did. Your vet will tell you everything else you need to know.