Hi Irene, 

-high insulin
-colicky episodes
-hamstring issues
-classic signs of PPID (loss of topline, long coat, etc)

Based on what I've read in this group, these signs all suggest to me that an increase in pergolide is warranted.  You might not be able to use ACTH as a marker for how well Logan's PPID is controlled (ie, if some or all of that ACTH value is from an inactive form of the hormone), and instead you need to look for improvement in the above signs to know whether his dosage is correct.  If he has high insulin (yes he does; share the above explanations for the Cornell insulin range with your vet), hamstring issues, and colicking problems these are things your vet should take seriously.  A trial increase in pergolide needs to be considered.  That's assuming that what you are already giving him is being stored properly and that he is getting the full dose...review his medication storage and dosing with the barn staff.

If your vet is not supportive, you might want to share with him/her the ECIR database on high pergolide dosages.  See this recent topic for more info:
https://ecir.groups.io/g/main/topic/69667617

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Kirsten and Shaku (IR) - 2019
Kitimat, BC, Canada
ECIR Group Moderator
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