best time to test acth and insulin


vicky monen
 

Hi,

I am trying to find the links for the best time  to pull labs for retesting/yearly testing the ACTH and the Insulin?  My guy is Cushings and Insulin resistant.  

Is it before the seasonal rise and then do you need to retest after the seasonal rise? 

If you can only afford to test once, what is better?
He is scheduled for next week.  This will be the first time testing for this year and I am just trying to figure out if this is a good time or should I just wait until the seasonal rise to see if I need to increase the pergolide?  He is at 2 mg/pills per day now. 

Thanks,
--
Vicky Monen and Samson

Aug 2015, Alpharetta Ga.

https://ecir.groups.io/g/CaseHistory/album?id=1226

https://ecir.groups.io/g/CaseHistory/files/Vicky%20and%20Samson


Sherry Morse
 

Hi Vicky,

Even now is cutting it close if you need to raise his pergolide dose and recheck it prior to the seasonal rise.  If you're not sure if he's well controlled, early to mid-June allows for test results to come back and dose changes to be made and checked prior to the seasonal rise for ACTH.  Insulin can be checked at any time but we usually recommend testing when the temperature is over 50F as lower temperatures seem to have an effect on insulin readings.




Kirsten Rasmussen
 

If you can only afford to test once, what is better?
If you can't retest a second time to check the dose increase, I would test in mid-July and increase accordingly.

--
Kirsten and Shaku (IR) - 2019
Kitimat, BC, Canada
ECIR Group Moderator
 
Shaku's Case History
Shaku's Photo Album


vicky monen
 

HI,

Seasonal rise is considered what months exactly? Aug through Dec? 

and how long after a dose increase should I recheck ACTH?

He is currently showing no symptoms, but obviously I need to test to make sure.  Also he never had high ACTH, only symptoms that suggested early cushings.  I usually have to go by symptoms since ACTH is always normal. Any other suggestions for dosage increase for these early cushings horses that test normal?  Currently the only cushings symptoms he is showing is long guard hairs and his coat grew in thick and fast after clipping in March 2021.  Otherwise he is looking great on the current dosage.  

Thanks so much,
--
Vicky Monen and Samson

Aug 2015, Alpharetta Ga.

https://ecir.groups.io/g/CaseHistory/album?id=1226

https://ecir.groups.io/g/CaseHistory/files/Vicky%20and%20Samson


Sherry Morse
 

Hi Vicky,

The seasonal rise starts with the summer solstice but has its most noticeable effect from August>October.  You can read more about this as well as see a weekly chart here: https://liphookequinehospital.co.uk/wp-content/uploads/Seasonal-Changes-in-ACTH-Secretion2.pdf.

You need to wait 3 weeks after a dosage change to recheck ACTH.

It doesn't look like you've ever used a TRH stim test on Samson, is that correct?  That might help you with checking to see if his dose is controlling his ACTH although there are no reference ranges for testing a horse on Prascend using the TRH test.  You may need to continue to rely on observation of symptoms with him.  Is he currently getting all of his Prascend in a single dose?




vicky monen
 

His dose is split up and he gets 1 pill in the a.m and 1 pill in the pm
Does that make a difference?

--
Vicky Monen and Samson

Aug 2015, Alpharetta Ga.

https://ecir.groups.io/g/CaseHistory/album?id=1226

https://ecir.groups.io/g/CaseHistory/files/Vicky%20and%20Samson


Sherry Morse
 

Hi Vicky,

We as a group have not found good success with splitting the dose.  The people who have done dosing twice a day are usually using the 2nd dose in addition to a high dose to help with continuous control.  You can do a search on this by going to the message list and putting "split dose" into the search box.



Carla Anderson Peters
 

Hello Sherry!
My pony has been on Prascend for a long time and the TRH stim test was just used to determine if the dose is appropriate. Did I read your response that this test isn’t appropriate for that?
Thank you!
Carla Peters
--
Carla

 

December 2013, WI

Cupcake and Gunnar's Case Histories 

Cupcake's Photos

Gunnar's Photos 

Ω



Sherry Morse
 

Hi Carla,

There is no reference range for the TRH stim test done for an equine already on Prascend. Once on Prascend you only need the basal ACTH reading to know if the dose is correct.




Eleanor Kellon, VMD
 

We don't have any studies on what happens to the TRH response when on pergolide - whether we should expect it to normalize or not.  It's probably reasonable to expect it to at least improve but we really don't know that. This is why it's not a very good tool for follow up at this point. However, if you have a horse whose signs/symptoms are worsening it's reasonable to repeat the test.
--
Eleanor in PA

www.drkellon.com 
EC Owner 2001


Carla Anderson Peters
 

Dr. kellon, you mean it would be appropriate to retest used in the endogenous ACTH test correct
--
Carla

 

December 2013, WI

Cupcake and Gunnar's Case Histories 

Cupcake's Photos

Gunnar's Photos 

Ω



vicky monen
 

I just went back and read the threads on splitting the dose.

Since I have been splitting his doses,  which might make it less effective,  is it possible he doesn't need the full 2 mg per day?

When switching him to his full dose once per day,  would I just give him the 2 pills and see if he gets a veil?  Or should I titrate him up to the 2 pills once per day? 

He had always been hyper sensitive to the prascend and any tiny increases cause the a bad veil, even on APF.  Thus the reason I began splitting the dose to begin with to a.m and p.m.  Now I wonder if I mistakenly done so and caused less effectiveness with my dosing.  

--
Vicky Monen and Samson

Aug 2015, Alpharetta Ga.

https://ecir.groups.io/g/CaseHistory/album?id=1226

https://ecir.groups.io/g/CaseHistory/files/Vicky%20and%20Samson


vicky monen
 

On Thu, Jul 8, 2021 at 06:55 AM, Sherry Morse wrote:
We as a group have not found good success with splitting the dose.  The people who have done dosing twice a day are usually using the 2nd dose in addition to a high dose to help with continuous control.  You can do a search on this by going to the message list and putting "split dose" into the search box.
I just went back and read the threads on splitting the dose.

Since I have been splitting his doses,  which might make it less effective,  is it possible he doesn't need the full 2 mg per day?

When switching him to his full dose once per day,  would I just give him the 2 pills and see if he gets a veil?  Or should I titrate him up to the 2 pills once per day? 
 
--
Vicky Monen and Samson

Aug 2015, Alpharetta Ga.

https://ecir.groups.io/g/CaseHistory/album?id=1226

https://ecir.groups.io/g/CaseHistory/files/Vicky%20and%20Samson


Sherry Morse
 

Hi Vicky,

The only way to know for sure would be to give him a single 1mg a day dose and then retest his ACTH in 3 weeks and see what it is.  Since we are currently heading into the seasonal rise I would not be willing to take that risk with my horse. 

As far as changing the dose to once a day I would just give him the 2 pills at once and if you think he is experiencing a veil you can add APF and go down to 1.5 for a few days and then go back to 2 pills.