http://www.smartgroups.com/message/readmessage.cfm?gid=1423922&messageid=3765 Yes, ferrets can and do get heartworms! Was the blood test (Idexx SNAP) positive for heartworms? If it is heartworms then there is 2 options. 1) Start on pediapred to reduce the inflammation in the lungs and to prevent blood clots. Plus start on ivomec to slowly kill the adult beartworms. Limit activity as much as possible. 2) Start on pediapred and treat with immiticide to kill the adult heartworms quickly. Limit activity. Lasix can be added if needed for congestive heart failure. Hope that helps, Jerry Murray, DVM [Posted in FML issue 4099]