Medication - Selegiline (Anipryl Rx)
I-deprenyl (Anipryl Rx)
Selegiline (Anipryl Rx)
Hyperadrenocorticism
and Selegiline (Anipryl Rx)
Selegiline (Anipryl Rx)
Anipryl for Cushing's disease
Anipryl for Cushing's
Anipryl
Anipryl for Cushing's
also see Treating cushing's with
Lysodren
also see Cushing's
page 2
also see Cushing's and liver enzymes
also see Cushing's and renal disease
also see Medication
l-deprenyl (Anipryl
Rx)
We have received several questions about the use of l-deprenyl (Anipryl
Rx) recently. This medication was approved this year for the treatment
of uncomplicated pituitary dependent hyperadrenocorticism (Cushing's disease).
In clinical trials this medication was effective about 80% of the time
in controlling this disorder but clinical improvement may take one to two
months. Since there are fewer reported side effects reported for l-deprenyl
than for mitotane (Lysodren Rx) there is a strong interest in its use.
As is the case with many new drugs, there are new problems relating
to its use. Perhaps the most perplexing to vets is the lack of a really
good way to monitor the success of treatment. Only a small percentage of
dogs will show improvement in the traditional laboratory tests used to
monitor Cushing's disease after treatment with Anipryl. This takes some
getting used to after years of carefully monitoring the effects of Lysodren
due to fears of toxicity. At present, improvement in clinical signs appears
to be the best way to monitor the use. This leaves a little uncertainty
that will make some vets and perhaps even some owners uncomfortable.
The other problem with Anipryl is that it is meant to be used in uncomplicated
cases of hyperadrenocorticism due to the need to reduce cortisol levels
quickly if diabetes or other complications are present. This is frustrating
to vets and owners who would really like to use a safer medication in these
circumstances. As time goes on protocols for use in some complicated situations
may be developed. Until then there are going to continue to be many cases
in which Anipryl use isn't going to be the treatment of choice.
Mike Richards, DVM
Selegiline (Anipryl
Rx)
Question: Dear Dr Richards,
First of all - THANKS for doing what you do! This is a truly valuable
service and I find it so helpful (along with my vet's advice of course).
I don't know if you remember, it's been awhile, but I have a lhasa named
Paris, 12 years young, who was diagnosed around Chrismas with a pituitary
tumor and
Cushing's. She did not do well on the first med we tried and she
almost died;
now she's on Selegiline. She's doing so well! I'm being
lulled into a false
sense that maybe she was misdiagnosed because she IS doing well.
I had read
several places that Anapryl doesn't work well....
I guess my question is, do you think she is improving? Is that
possible? I
know the tumor isn't going to go away, and I'm ecstatic that she's
doing
well, but I'm afraid I'm in denial about the possiblity that she's
really OK.
Thank you so much!
Roxanne
Answer: Roxanne-
Selegiline (Anipryl Rx) is a medication that seems to have veterinary
endocrinologists choosing up sides and issuing lots of strong opinions.
I
have a couple of textbooks that suggest it shouldn't be used at all
and a
couple more that think it will help a lot. The most recent information,
pretty much the only study not funded by the companies that produce
selegiline, is that it works really well in about 20% of dogs, OK in
another 20% and doesn't work well at all for the remaining 60%, when
treating hyperadrenocorticism (Cushing's disease). In the dogs
in which it
worked, it did appear to slow or arrest the growth of the pituitary
tumor,
so that was a strong incentive to consider use, especially in the subset
of
dogs with the tumor type it appears to work best for which was identified
by MRI exam.
There is another complicating factor with the use of selegiline.
It is
also used to treat canine cognitive dysfunction and it is highly likely
that many patients with Cushing's disease also have canine cognitive
dysfunction, since the diseases are most common in the same age groups.
So
some of the perceived improvement is potentially due to a concurrent
problem.
There really isn't a good way, other than observation of clinical signs,
to
tell if selegiline is working well. Since people do want to get results,
there is always the potential for a placebo effect in these evaluations.
Most veterinarians feel that a dog with laboratory evidence of Cushing's
disease but no clinical signs does not require treatment, though ---
so
when looking at the use of selegiline from this perspective it seems
reasonable to try it and to continue to use it as long as it does appear
to
be controlling the clinical signs of the disease. If it stops appearing
to
work, that would be the time to worry.
Mike Richards, DVM
10/9/2000
Hyperadrenocorticism
and selegiline (Anipryl Rx)
Question: Dr Mike, just skimmed the September digest and noted
with some fear that
your described hyperadrinocorticism is a 'serious' condition.
'Sweetie'
is/has been treated with Anypril for what was diagnosed as 'pituitary
dependant' hyperadrinocorticism. I wrote to you a a couple of occassions
re:
dosage etc. I monitor her carefully but did not know the condition
was
considered 'serious'. Would you please claify for me ?
She has been on
medication for several months but I have not had a follow on blood
test -
and probably should have.
Answer: Bruce-
If it is not controlled hyperadrenocorticism causes a lot of problems
that
can become serious, including an increased susceptibility to bladder
infections, skin infections, diabetes, heart disease, respiratory disease,
seizures and a number of other conditions. Due to the association between
pituitary brain tumors and hyperadrenocorticism, it may be fatal even
in
treated patients, since the treatment does not do anything for the
presence
of the tumor. So these are the reasons that the condition is considered
to
be serious.
It is very early in the understanding of how selegiline (Anipryl Rx)
works,
but there is some chance that it may decrease the rate of groth of
some
pituitary cancers from overstimulation by the hypothalamus.
On the other hand, the first independent study of selegiline that I
know
of, by Dr. Peterson, suggests that it is only helpful in about 40%
of dogs
and only highly successful in 20% (small sample size -- 10 dogs).
This is
lower than the reported rate of success from the manufacturer's studies
but
due to the relative safety of this treatment, it still seems reasonable
to
me to use it until it doesn't seem to be working, based on an increase
in
clinical signs such as increased drinking and urinating, panting, weakness,
hair loss, concurrent diabetes or increased susceptibilty to infection.
It is hard to monitor the success of selegiline with blood tests, so
there
probably isn't any problem with not having that done. It would be a
good
idea to have periodic evaluations by your vet to ensure that there
are not
clinical signs that are suggestive of the need to re-evaluate treatment,
though.
Hope this helps some.
Mike Richards, DVM
9/14/2000
Selegiline (Anipryl
Rx)
Question: Doctor, I have been treating 'Sweetie', a 14 yr.old
Shelty mix, for
Cushings Disease for approx. 60 days. She is approx. 23 kg.
and have been
giving 15 mg. Anipryl daily. Diagnosis was made using low dose
Dex
suppression followed by ACTH. The Dex suppression was not positive
and ACTH
was "high normal"
Symptoms were: fur not regrowing after clipping, high water consumption
and
heavy panting in cool weather.
Her fur started to re-grow after two weeks of medication and water
consumption went down but she still pants quite a bit even in the house
when
it is cool. She prefers to lay on the tile floor. One large place
(length
of my hand and 1/2 the width) on her side the fur has not re-grown.
My vet
says stay the course with the Anipryl for a month or more and bring
her
back. Her health in general is great. What additional recomendations
would
you make if any.
Bruce
Answer: Bruce-
The recommended dosage for selegiline (Anipryl Rx) is 1mg/kg for a starting
dose. If there is no improvement, or insufficient improvement, in clinical
signs within 60 days then the recommendation is to change the dosage
to 2
mg/kg.
If Sweetie is 23 kg, she is being underdosed currently, based on the
recommended dosing. If she is 23 lbs, she is being dosed in between
the
lower and higher dosage recommendations but there is still room to
increase
the dosage to about 20mg and to stay within the guidelines.
I would recommend trying a higher dosage before trying an alternative
approach to treating the Cushing's disease, since you are getting at
least
a partial response. This is probably what your vet is planning on.
I can
see why your vet is tempted to stay at a lower dosage with the amount
of
improvement you have seen so far, though. But there is room for increasing
the dosage safely to try to resolve the remaining clinical signs.
Mike Richards, DVM
4/6/2000
Anipryl for
Cushing's Disease
Q: Dr. Richards,
Thank you for your response to my first E-mail.
I took Ruby back to the Veternarians office on Friday. I was concerned
that she was loosing more weight. She weighed in at 4.6lbs. She
has
lost almost .5lb in a month. Very skinny.
I took your E-mail with me.
The Veternarian performed many tests:
He performed a pre-ansthestic test. It came back on the low side
of
normal. Doesn't this test give information on how the kidneys
and the
liver are functioning? If she has a liver shunt wouldn't you
expect to
have an abnormal test result?
Re-tested her ammonia level, within the acceptable range.
Since this Vet has the cababilities to perform the ACTH test in house
I
request that it be redone. I am not sure of the unit measurements,
but
her base level was 10. Too high I was told. After
the administration
of the Cortsol it was 25. Also too high. Therefore, he concluded
she
had Cushing's disease. Does this sound correct?
He also ran a urine test. He found no sugar, but he called it
dilute.
He said this was common for a dog with Cushing's disease.
I was reading that HAC is usually caused by an underlying benign and
often microscopic tumor in the pitutary gland which secretes excessive
quanitites of ACTH. Would it make sense to go ahead and
test for
Hypothyroidism since the thyroid hormone is under the control of the
pituitary gland? I also read that with Hypothyroidism the hair
is
easily pulled out by the root. Ruby's hair pulls out very easily
when
I give her medication. If it is Hypothyroidism what types of
medications do they have available? Will she put on weight eventually?
Is it common for a dog to get Cushing's disease if they have
Hypothroidism? What kind of life span with these two diseases could
be
expected?
This last month we placed Ruby on Science Diet K/D, since we thought
she may have a Liver shunt. Now she has lost .5lbs. Her ammonia levels
are normal. Should we wait until we have the results to the Bile Acid
Response test before placing her back on Eukanuba?
We place Ruby on Anipryl for Cushing's Disease. He said it was
safer
than the other medications available. What is your thought? Should
we
use a more aggressive medication?
Thanks again, Heidi
A: Heidi-
The lab values you report for cortisol (pre ACTH stimulation level of
10
and post ACTH stimulation level 25 are indicative of hyperadrenocorticism
(Cushing's disease). At this time, I prefer to start with l-deprenyl
(Anipryl Rx) in cases of uncomplicated hyperadrenocorticism, too. Some
of
the clinical history that was in your original letter is not typical
of
hyperadrenocorticism but there are a lot of variations in the observed
clinical signs with this disease. Most dogs have increased drinking,
increased urinating, increased appetites, pendulous appearance to their
abdomen, hair loss, thinning of the skin and sometimes itchy skin sores.
Not all dogs exhibit all symptoms and some have different or even no
symptoms.
It is not unusual for dogs with hyperadrenocorticism to also have
hypothyroidism. It is a little difficult to interpret thyroid tests
until
the hyperadrenocorticism is under control but if you wish to do testing
for
this it would be best to use the free T4 by equilibrium dialysis and
canine
TSH levels to evaluate the possibility that hypothyroidism is present.
The continued weight loss is worrisome. Dogs usually don't lose much
weight
on k/d as it is not calorie restricted, just protein and phosphorous
restricted. There wasn't much in the labwork to indicate other problems
except the mild elevation in BUN (which is associated with kidney
disorders) and the dilute urine --- which could be from
hyperadrenocorticism or could be from an inability of the kidneys to
concentrate urine. I would probably be tempted to retest the blood,
at
least the values related to kidney function -- BUN, creatinine,
phosphorous, potassium and total protein levels. Often, it is necessary
just to run a whole blood panel to get these tests, since most of the
"mini" panels leave at least one out.
It is unusual for a liver shunt to be initially diagnosed in a dog that
is
Ruby's age. Not impossible, as I know of at least one older dog we
diagnosed in our practice but it just seems like signs usually show
up much
earlier. So I guess with the lab work I would be comfortable not worrying
about that possibility too much.
Hope this helps.
Mike Richards, DVM
5/3/99
Anipryl
Q: Tonight must be my night. My dog, a 6 y.o. Lab/Ret
mix was recently diagnosed with pituitary-dependent Cushing's Disease in
May 1997. One question I have is I do not understand why when he weighs
96 pounds and is given 2.5 mgs. of Cortisone he has an allergic reaction.
Because he is so sensitive to so many drugs and has chronic colitis in
addition, he was started on 45 mgs. of Anipryl. His specific gravity in
the beginning was 10.07. After being on the Anipryl for one month, his
specific gravity increased to 10.11 but then after the next month it went
down to 10.7 again. He was therefore increased too 90 mgs daily. Unfortunately
his specific gravity is hovering around 10.08 and he has little to no hair
regrowth. What I do not understand is when he is taking 45 mgs. of Anipryl
he is like my old puppy....so playful....water intake decreases...his appetite
has decreased, etc and he is not urinating for long periods of time. Because
his specific gravity did not come up to at least 10.15, my Vet wants to
start Lysodren. I feel like if I do this, I will be taking so much away
from my dog. It's like he has his life back. I have heard so many horror
stories about Lysodren that I'm scared to death of what will happen. I
just hope that either you may be able to help me or direct me to someone/someplace
that might be able to.
Thank you for your time. Linda
A: Linda-
I am under the impression that Anipryl (Rx) does not always change the
laboratory values much and that it is best to evaluate its effectiveness
based on clinical signs rather than lab testing, as is normally done with
other medications used to treat Cushing's disease. I think it would be
a good idea to ask your vet to call the manufacturer of Anipryl and ask
their technical support vets about this. If your vet is a member of the
Veterinary Information Network there is information in the database on
monitoring dogs on Anipryl but none of it directly addresses the use of
specific gravity as a monitoring tool. I have not used Anipryl, nor purchased
it, so there is a chance that your vet is following a protocol included
in the package labeling that I am not aware of.
Sorry I can't be more help.
Mike Richards, DVM
Anipryl for Cushing's
Q: Dr. Mike My 8 year old dog Ebony was diognosed
with Cushings 1 month ago.He has had his daily doses of Mitotane and is
on therapy now.(1/2 tab.500mg twice a week.) I'm unhappy that this drug
kills off the adrenal gland.I fear that he might get Addisons disease.
There is a new drug in Canada called ANIPRYL that sounds so much better.(www.deprenal.com/Brochure.htm#ANIPRYL)
Do you know of this drug or anyone that has used it? Do vet Schools use
it in studies? I wonder why the FDA has not approved it here yet? It sounds
full of promise for not only cushings but cognitive dysfuction. I don't
want to think that Ebony only has 2 years. Do you know why they give that
figure and what happens at the end of that period? Anipryl effects the
problem, Pituatary dependent, rather than adrenal gland. Can you help with
ANY information? Thanks for your time.
A: The use of l-deprenyl (Anipryl Rx) is under
investigation in the U.S. for treatment of Cushing's disease. There is
a good article on this in a recent Clinics of North America, "Adrenal
Disease" -- I am not sure of the exact issue but it was very recent.
Dr. Dave Bruyette has been involved in much of the study of this
medication in the United States. I think that he would be willing to talk
with your vet about use of this medication. I will try to locate contact
information for you if I can.
Mike Richards, DVM