Text Box: Intestinal Parasites Text Box: These photos are of roundworms. Round worms are very common in both cats and dogs. Intestinal worms can cause vomiting, diarrhea and malnourishment. Other types of common intestinal parasites include hookworms, whipworms, and tapeworms. Round worms and Hook worms can be transmitted to people. Text Box: It is important to treat and prevent intestinal parasites in your pet. We can help you do this at an affordable cost.