Next steps adjusting pergolide: getting my vet on board


 

I wrote several weeks ago that Satra's ACTH tested on Oct. 19 at 12 pmol/L. Susan kindly converted pmol/L to pg/ml at 54.48 pg/ml.

Satra has been on 1 Prascend for about a month. She is apparently compensated IR (need to pick up test results). Satra is no longer footsore, the symptom that lead to the testing and diagnosis. She still has a long, silky coat (it's winter), and she is pot-bellied (former broodmare). She also drinks almost twice as much as my other mare and urinates accordingly. She has a strong appetite - not quite ravenous, but often acting hungry. That's the sum total of her symptoms.

When I asked my vet to do a follow-up ACTH test now that Satra has been on Prascend for a month, the response was that we should titrate dose based on clinical signs, as opposed to test results. Fair enough: I accept that I should administer pergolide if Satra still has symptoms with a normal ACTH result. But if Satra still has the most obvious PPID symptoms and her ACTH remains elevated, how can I know her dose is inadequate without testing? My vet seems to be under the impression that ACTH will never again be normal, even on pergolide. Is that correct? I garnered this from Files, don't know where:
"The effective dose is that dose which controls ACTH to below---
6.38 pmol/L (29 pg/ml) Nov - July
10.34 pmol/L (47 pg/ml) Aug to Oct."

Don't we need a follow-up ACTH test to know if the dose is adequate to control ACTH? Is hirsutism ever going to improve if ACTH is within the above ranges? The water consumption? The pot belly? The appetite?

In my vet's practice, minimal intervention is a common necessity, and I don't fault that approach. Thank goodness, I can do more than the minimum. I don't want to risk full blown laminitis for the lack of a blood test!

I want to provide my vet with research and references. Suggestions? An article published in a professional journal on titrating pergolide and reference ranges for controlled ACTH would be a start.

TIA.

Cass for Satra
Sonoma County, Calif
Oct 2012
http://pets.groups.yahoo.com/group/ECHistory6/files/Cass%20for%20Satra%20-%20Northern%20California/


merlin5clougher <janieclougher@...>
 

Hi, Cass -

The goal in managing Cushings horses is to get the ACTH into the mid- or low-normal range, as well as control the symptoms. I think testing is absolutely ideal if you can afford to do it. She is still showing symptoms, so increasing the pergolide even without a test is reasonable. What about increasing (incrementally) to 2 mg, and then testing 3 weeks later?

The drinking/peeing should most definitely improve (usually within a few days of hitting the right dose, and almost certainly within 2 weeks of hitting the right dose); the pot-belly takes a bit more time, as there needs to be some muscle rebuilding; the hirsutism is variable, and some horses always have a bit of that.

Have a shufti around pubmed, and see if there is anything there:

http://www.ncbi.nlm.nih.gov/pubmed


Your vet is probably gobsmacked that someone wants to spend money!

Jaini (BVSc),Merlin,Maggie,Gypsy
BC09
EC mod/support

http://pets.groups.yahoo.com/group/ECHistory/files/Jaini%20Clougher%2C%20Smithers%20BC/

--- In EquineCushings@yahoogroups.com, "cass_sonomacounty_ca" <cbernstein@...> wrote:

Don't we need a follow-up ACTH test to know if the dose is adequate to control ACTH? Is hirsutism ever going to improve if ACTH is within the above ranges? The water consumption? The pot belly? The appetite?


Cass for Satra
Sonoma County, Calif
Oct 2012
http://pets.groups.yahoo.com/group/ECHistory6/files/Cass%20for%20Satra%20-%20Northern%20California/


 

Aha! Thanks, Jaini. That sure helps. I thought I noticed initial improvement in the drinking and urinating, but there's been a definite backslide. It's not easy to monitor drinking and urination when the horse isn't stalled. I'll taper up the Prascend to 1½ or 2 and see what happens.

Cass for Satra
Sonoma County, Calif
Oct 2012

--- In EquineCushings@yahoogroups.com, "merlin5clougher" <janieclougher@...> wrote:
She is still showing symptoms, so increasing the pergolide even without a test is reasonable. What about increasing (incrementally) to 2 mg, and then testing 3 weeks later?

The drinking/peeing should most definitely improve (usually within a few days of hitting the right dose, and almost certainly within 2 weeks of hitting the right dose); the pot-belly takes a bit more time, as there needs to be some muscle rebuilding; the hirsutism is variable, and some horses always have a bit of that.


 

Jaini suggested, " What about increasing (incrementally) to 2 mg, and then testing 3 weeks later?"

Jaini, I have now definitely seen a considerable change in Satra over the past 3 days. She is drinking just a bit more than her companion, who is a full hand shorter. Her stall is no longer a swamp. And today she treated me to airs above ground and repeated gallops around the corral. She's clearly feeling better. We topped out at 1.5 mg pergolide. Thanks again! On to the next challenge: a vet willing to do the Cornell testing. I'm in a data blackout.

Cass for Satra
Sonoma County, Calif
Oct 2012