Kevin - there are no drugs that will eliminate a viral infection (the most likely cause) or render it intransmissible. All you can do to prevent spread is quarantine, and be very careful yourself not to handle the uninfected animals after the infected ones. I generally do not recommend any specific drugs to treat the congestion unless the animal is so stuffed up that he won't eat. With kindest regards, Bruce H. Williams, DVM, DACVP Join the Ferret Health List at http://groups.yahoo.com/group/Ferret-Health-list [Posted in FML issue 3358]