When ferret hearts have trouble with Pred it tends to mean that there
was already heart disease in place. Dilative cardiomyopathy is the
most common, but hypertrophic cardiomyopathy can be hard to spot
without an ultrasound (sometimes completely impossible to spot without
ultrasound), and there are other heart problems they can get such as
A/V Heart Node Blocks, rarely a heart tumor (also tends to be hard to
spot), heart worms (can also be hard to spot), etc.

Usually when there is heart disease Pred is not used unless there is
not a choice and then the amount is minimized by using some digoxin
along with Prednisolone (not Prednisone). The ferrets for whom Digoxin
works for insulinoma can use less Pred. The reason for Prednisolone
rather than Prednisone is because the liver has to process Prednisone
into Prednisolone before the body can utilize it. If the liver is at
all compromised then the dosage needed with Prednisone will be higher
than the dosage needed for Prednisolone.

In 30 years with ferrets and a lot of that time spent helping people
get veterinary care for ferrets I have never heard of a ferret heart
having trouble with Pred except when there was pre-existing heart
disease.

Your description reads like undiscovered heart disease. Coughing in a
ferret is a BAD sign and worse when combined with lethargy. It often
means there is heart disease or ascites from another serious cause,
and sometimes means there is pneumonia.

We usually try to get to the vet the same day when coughing starts, but
that is because we had one who never coughed and then one day began to
cough. She sounded fine when the vet listened, but this was not the
ferret vet so we insisted and an x-ray was done. The next thing we
knew, the vet we'd seen was pulling the ferret vet from an appointment
temporarily. The x-ray showed an opaque chest. Our ferret had both
pneumonia and pleurisy and probably would not have lived another day
without treatment. BTW, she also had an emergency ultrasound the next
day and was put on two antibiotics immediately. So, we are big fans of
prompt chest imaging for ferrets who have worrisome coughs.

Sukie (not a vet)

Recommended ferret health links:
http://pets.groups.yahoo.com/group/ferrethealth/
http://ferrethealth.org/archive/
http://www.afip.org/ferrets/index.html
http://www.miamiferret.org/
http://www.ferrethealth.msu.edu/
http://www.ferretcongress.org/
http://www.trifl.org/index.shtml
http://homepage.mac.com/sukie/sukiesferretlinks.html
all ferret topics:
http://listserv.ferretmailinglist.org/archives/ferret-search.html
"All hail the procrastinators for they shall rule the world tomorrow."
(2010, Steve Crandall)
On change for its own sake: "You can go really fast if you just jump
off the cliff." (2010, Steve Crandall)

[Posted in FML 7029]