Which medicine do you use to deworm your pet? Most pet owners vaccinate their dogs, administer fumigants to remove parasites and take them to the vet to operate on a fractured femur but forget the crucial aspect of deworming. Dogs like scavenging for scraps of food and may in the process ingest the eggs of various parasitic nematodes. The most effective antidote against them is mixing dried tobacco leaves or powder with their favourite food. The worms will be dispensed with in a matter of hours. It really works.