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A while back, someone wrote to me asking
questions about Lupron. Through this exchange, I learned that a pharmacy and vet in the Midwest is promoting
24 hour Lupron with the claim that it is effective
for one month. I was surprised to hear this and
didn't believe this claim to be true, but since I'm not a vet or
pharmacist, I thought it best that I do some research before
disputing this claim.
I tried to get a better explanation from the vet and
pharmacist prescribing this Lupron, to no avail. In their defense, I did not
speak to them directly but through a second party. The only thing I knew was the
claim that the 24 hour Lupron worked long term because of, "the way it attaches to the adrenal
receptors." I was looking for a little more detailed explanation how this works
for a period longer than 24 hours but was never offered any more than that.
I wrote to several vets I know and the response I got was that 24
hour Lupron works for
24 hours, period. That was appreciated but their response did not include any
detailed explanation as to why it could not work as claimed.
I then contacted John Hines, who wrote, "Adrenal
Disease and the Therapeutic Effect of Lupron." Since John studied the topic of
Lupron usage, has a Ph.D. in Pharmacology and is a ferret lover, I felt I wouldn't find anyone more
knowledgeable on the subject and definitely one with the credentials to offer an
expert opinion.
First a brief layman's description (mine) of how Lupron works
so some of John's comments might make a little more sense. Lupron desensitizes
the pituitary gland and causes it to stop producing two hormones, LH (luteinizing
hormone) and FSH (follicle-stimulating hormone). These two hormones
(the primary problem is LH) stimulate the adrenal glands into producing sex
hormones which cause the adrenal disease symptoms we see. This is an extremely
basic explanation. There are many more details in John's paper.
My main question to John was, can 24 hour Lupron be effective
in ferrets for adrenal disease treatment if used as a monthly dose? John's
comments on the topic were as follows:
"... if the Lupron is of the type that all enters the
bloodstream in 24 hrs., (24 hr. Lupron) what you get is a few hours of high
pituitary activity followed by only several HOURS of inactivity (desensitized).
Then the 24 hr. Lupron is gone shortly thereafter, and the pituitary
RE-sensitizes and LH release to the natural GnRH resumes probably in a day or
so. If the ferret is only getting the 24hr. shot once a month, it's useless. In
fact, the use of the 24 hr. Lupron probably makes the adrenal disease worse
because you don't get much therapeutic effect, but you are still getting that
initial high pituitary activity when the Lupron is first administered. This
initial burst of pituitary activity is of little consequence when it is followed
by cessation of pituitary activity. But, with the 24 hr. Lupron, you get only
the initial burst of pituitary high activity -- followed by normal pituitary
activity. It's like adding a splash of gasoline to a fire."
We had several discussions, particularly about the claim
that the 24 hour Lupron works for a month or more because of "the way it
attaches to the adrenal receptors" to which John responded:
"I did notice in your earlier correspondence that the vet
and pharmacist had described their Lupron as binding to 'adrenal receptors'. I
can see how a drug that binds to the pituitary and impacts on the adrenals could
be misconstrued as binding to the adrenals by the average person; however, if
the pharmacist or vet actually said to her that "Lupron binds to adrenals", then that immediately is cause for
concern as it demonstrates a fundamental ignorance about how the drug works."
"[pharmacist's name omitted] doesn't understand how Lupron
works. He seems to know what its ultimate effect is, just not the mechanism.
That's a shame, because he should know better than anyone. Leuprolide binds to
receptors on the pituitary. The word "attach" could be misleading -- to some
people it might imply a permanent joining of the leuprolide to the GnRH
receptor, which is not the case. Leuprolide tightly associates ("binds") with
the GnRH receptor, but it is a reversible process. It can dissociate ("unbind")
as well."
I know that the vet offering 24 hour Lupron does a lot of good for ferrets and I
understand the intent is to offer an affordable alternative for treatment of
this all too common disease. Does 24 hour Lupron work in some cases? Several
people have claimed that it does.
What worries me, besides the fact that this type of Lupron may not work, is that
after hearing John's explanation, realizing that there is also the chance it
could make the condition worse.
The important message I want to get across is, ask questions,
know what you are getting and what you are treating your ferret with. This
applies to ANY treatment, not just one for adrenal disease. In this case, I was
told by the person that contacted me that she was not told that what she was
getting was 24 hour Lupron, only that it would work for a month or so. I am
fairly certain that if the vet had been asked directly, "Is this 24 hour Lupron?" or
"What formulation of Lupron is this?" the vet would have been honest and
upfront. Vets (even human doctors) often don't give us all the information
unless we specifically ask for it. So don't be afraid to ask. The type of Lupron
that is a genuine, time-release formulation is called Lupron Depot. This comes
in three formulations: 1-month, 3-month and 4-month.
If 24 hour Lupron is something you want to try for
whatever reason, this probably won't change your mind. Just be aware that you
may see no results and in fact, may make matters worse.
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