Prescription items are NON-RETURNABLE and NON REFUNDABLE Tamiflu Capsules Tamiflu is a human antiviral medication used in the treatment of parvovirus in dogs. It is an active neuraminidase inhibitor that hinders the release of viral particles from cells that are infected by bacteria. Oseltamivir phosphate, the active ingredient in Tamiflu, attacks parvo and prevents it from spreading. 012RL01-75X10 300040800852