Should I and how much should I increase Pergolide due to seasonal rise? Are "bad" ACTH samples readable at all - can they show a lower value?


Hi all

My horse was diagnosed with Ppid in november 18 and was prescribed 1 mg of pergolide daily to start with. In the end of February I took a new ACTH test and my vet. sad he was well within normal ACTH values on that and that I could carefully try to introduce him to a forest/hilly area with little grass, with a few other geldings. I did so in the end of April but quite soon I found out that his crest started to grew abnormally, and that he was a little tenderfooted (no pulse, no reluctance to turn, only slightly tenderfooted) so I moved him to a completely grass free area and he got better. But in June I saw that his summer fur continued to grow and in the end of july another vet. took a new ACTH blood test which I haven't got an answer to yet. But she said that the way he looks with the long fur and a little bit pot bellied, she thought that I could increase the pergolide with 0,5 gram. And I did so the 25 of July. 

I find him calmer and a little bit more picky with the food. The long fur is still there and I consider to cut him. It is still warm here in Sweden and the fur might make him too hot. Or will he drop it soon?

Now I wonder If that increase is enough or if he should have more pergolide due to seasonal rise which have started now? 

As I said I can't get an answer from the vet regarding the ACTH value. She has not been available at all lately (maybe sick?). She also said when I met her in July, that a lot of ACTH test get bad on the way to the lab because they get too hot (it should be sent frozen and delivered early next day but the mail service is not reliable and since the lab is in another town 500 km away it is not possible to send it with an express agency). So I'm afraid that the sample has gone bad and she bcs of that has no answer to give me.

So here is some things that I have been thinking of lately

Is it possible that the sample from February was bad? Does bad samples show lower values or are they just unable to read? I wonder because my vet said he was "well within normal values" but still he grew a longer summer fur. Or do they always grew longer fur when they have Ppid?

Should I increase Pergolide more because of seasonal rise? If so when and by how much? (I'm terrified he will get laminitis since he recently recovered from it). 

Do I need to take a new blood sample? When?

I have just started to fill in my case history form so please excuse me that it is not complete 

Best regards


Lorna Cane

Hi Sylvia,

Thanks for starting on your CH. The more details that you have time to add,the better advice we can give.For example, the test results for your tests are important.And the weights of feed ,other than hay, being fed. How much beet pulp,etc.?
His weight does sound a bit high for a horse his size, so diet may be something to consider.Not sure.
It is possible your blood samples were spoiled if they did not arrive at lab frozen. I would think the lab would have commented on that though? In any case,results are usually lower than normal if samples have been mishandled.
One of our vets will have something to add.

Can you go back to where you made your automatic signature and add your location,and your joining date to your name and CH link(thanks for those)? Don't forget to scroll down to Save.
That would help us help you better.

Don't be terrified. You're on it  for Sputnix, and we just have to get more details nailed down.


Lorna  in Kingston, Ontario, Canada
ECIR Moderator