From:
Roger Vaughn
Date: 2002-01-02 21:47:00 UTC
Subject: Re: [Ferret-Health-list] Bilateral adrenals: why
prednisone?
I'm not a practitioner, but this info is based on research I've done
after receiving various steroids for both myself and my pets. I can't
answer specifically why vets choose pred over dex, but this info may
help you understand the issues.
Both are corticosteroids, or more properly glucocorticoids. This means
little to us non-pharmacologists, but the gist is that this entire
group of compounds, also including cortisone and hydrocortisone, are
used medically for their anti-inflammatory properties. Each one has
important differences, though, one of the most important of which is
half-life. No, they aren't radioactive, but they do break down in the
body over time.
Prednisone has a relatively short half-life - only a few hours - and is
flushed out of the body relatively quickly. This helps to prevent a
build up in the body when given daily. It is converted to prednisolone
in the liver and apparently mimics the body's own steriods fairly well.
Dexamethasone is much stronger and has a much longer half-life - on the
order of 3-4 days. It sticks around much longer, and daily doses will
tend to accumulate more in the body than will pred.
The two - and all of the corticosteroids - have other effects on the
body, and differ in what those effects are. In general it is not safe
to take any corticosteroid for extended periods, though ferrets seem to
tolerate them well, and in cases like bilaterial adrenalectomy, you
have no choice but to supplement the body with external steroids.
So it would appear that in most cases, dex is overkill for simply
reducing inflammation. For adrenal cases, though, you'll have to ask a
doc why.
Here are a couple of good sites explaining various meds. One is for
veterinary meds and the other for human meds.
http://www.marvistavet.com (go to the pharmacy section)
http://www.medsafe.govt.nz (go the health professionals section,
medicines list)
I have no affiliation with either site - I simply found them through a
web search.
Roger
Digger and Bear