Hi Kay,

Please read the Diagnosis section of Bobbie's email to you and make a plan with your vet before he arrives.  The reason glucose was so low is because her blood was not handled correctly.  This will artificially lower the insulin and ACTH, too, although not as dramatically.  Immediately after pulling it, it needs to go on ice or in the fridge.  It must be centrifuged within 4 hrs then frozen overnight (longer is ok) and shipped to the lab with ice packs on 1-day delivery.  It needs to arrive at the lab chilled and on a weekday so it can be received.  My vet will often freeze it over the weekend and send it out on a Monday.

Thyroid hormones are often low in metabolic horses due to euthyroid sickness.   This is due to the metabolic issues, not a diseased thyroid, so the best fix is to deal with the metabolic issues.   Thyro-L will cause weight loss, which you don't want, and it will depress the natural thyroid function so it needs to be weaned off of very slowly. 

A safe bagged feed are the Triple Crown Naturals Timothy Balance cubes (aka Ontario Dehy Timothy Balance cubes), if you can source them.  They are guaranteed to be below 10% sugar+starch, are fully mineral balanced, and because they are higher in calories they are fed at a rate of 75% of the hay you are feeding, by weight.  All you need to add is 2-4 oz ground flaxseed, 2000 IU vitamin E, and salt to have a complete diet that is safe for a metabolic horse.

She was started off immediately on 1 pill a day and never experienced any side effects or problems till most recently, the last few weeks is when all of the issues got worse. 

Conjecture here, but if her behaviour changed recently on Prascend, and she was doing well before on 1 mg, it's likely that she needs a higher dose because the seasonal rise is started.  I would restart it and work on increasing the dose until her behaviour and other signs (like excessive peeing) normalize.  The abnormal fat last fall may have been the fat pads and cresty neck associated with uncontrolled PPID.

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