Centragard (eprinomectin and praziquantel transdermal solution) is a monthly heartworm disease prevention product for cats that is applied topically. It is also approved to treat and control three of the most common intestinal parasites of cats: hookworms, roundworms and tapeworms. According to product developers, Centragard is the first product to protect against this spectrum of parasites in an easy-to-use transdermal formulation. It's approved for use in cats and kittens as young as 7 weeks of age weighing at least 1.8 pounds and features a unique transparent applicator, giving cat owners more control when applying the product. As a transdermal product, Centragard should be administered topically. If ingested, cats may experience hypersalivation, vomiting and lethargy.