cushings · Uncategorized

Pergolide v Prascend

Longer blog readers will remember that Tristan has Cushing’s disease, or more accurately pituitary pars intermedia dysfunction, PPID. He was diagnosed a number of years ago based on observed symptoms and then a blood test. We started him on 1mg daily of compounded pergolide and he responded beautifully. He’s been on that pergolide for several years now, and is maintaining well. I’ve written regular update posts about that.

Last week, I reached out to my vet to renew Tristan’s pergolide prescription at Wedgewood Pharmacy, since he was running low, and she gave me some bad news.

See, for a long time, the only way to get pergolide was just the way that I was buying it, through a compounding pharmacy. “Compounding” just means that they follow the recipe for mixing up a drug and then make that drug and sell it. The pergolide they were making was actually mixed up for humans and prescribed off-label for horses. As I understand it, the FDA agreed to allow this because there was a demonstrated need.

A few years ago, a company called Boehringer Ingelheim developed, tested, and patented an equine-specific formulation of pergolide. They put it into a pill form and named it Prascend. The new drug offered some good benefits: it could promise a more accurate dosage, in pill form it might be easier to feed, and it had jumped through all the hoops and so on.

Tristan was doing just fine on the compounded pergolide, and I had no intention of moving him to Prascend. It was in the back of my mind but seemingly unnecessary.

Until last week, when my vet filled in the last piece of the puzzle. As soon as Boehringer Ingelheim put Prascend on the market, that meant that technically the off-label use of compounded pergolide was no longer allowed by the FDA. A lot of vets still prescribed it, because it worked just fine and for many, even most horses, there was no medical reason to switch.

But the company has been putting pressure on vet boards to remind vets that they’re technically not supposed to prescribe the compounded pergolide, and my vet has decided that she can no longer prescribe it. I totally support her decision. I adore her and she’s saved Tristan’s life on more than one occasion. Reading through the PPID groups, it seems there is a legal basis to challenge and keep him on the pergolide, but it’s not without risks and is a huge pain, and I don’t want my vet to have to deal with any of that. So he’s switching to Prascend.

Here’s the catch. Of course there’s a catch. I wouldn’t be writing a long-winded blog post if there weren’t a catch.

I was paying $0.55/day to keep Tristan on pergolide. Because Prascend has the market cornered, the cheapest I can find it is $1.75/day. That means an increase from $200 a year to about $640 a year. That’s assuming he stays stable on 1mg a day – which is not a safe assumption. Cushing’s is a progressive disease and it could easily – and probably will – require an increased dosage to keep him happy and healthy.

Horses are expensive, and I got this news literally about two hours after writing my first Finance Friday post and scheduling it. I went through all the stages of grief, and landed on acceptance after a few days.

Tristan gets what he needs, always. That’s not in question. I’ll figure out a way to pay for it. But wow, do I feel kind of sucker punched right now. He was doing fine on the compounded pergolide, and the only reason we have to switch now is because of a drug company’s greed.

15 thoughts on “Pergolide v Prascend

  1. So annoying! I actually sent this to some vets at work to see their thoughts on any options you had and we did some research… Prepare yourself…

    Check out this answer from AVMA (

    Q: When is ELDU used/necessary?

    A: Extralabel use is limited to circumstances when the health of an animal is threatened, or suffering or death may result from failure to treat. As we’ve already stated, extralabel use to enhance production is prohibited.

    Examples of clinical circumstances in which ELDU might be employed/necessary are listed below:
    A dog is diagnosed with congestive heart failure by its veterinarian, and furosemide administration is part of the therapeutic plan. There are FDA-approved products labeled for use in dogs, including brand name and generic products, but the veterinarian recommends the human product from the local pharmacy for economic reasons. A prescription for ELDU of the human product is acceptable in this circumstance.

    However, further down the page…
    “Deviation from ELDU regulations is an illegal action subject to prosecution by the FDA. The spirit of AMDUCA is to allow veterinarians flexibility in administering drugs that will help relieve animal pain and suffering. The overarching premise of the law is that extralabel use is acceptable when filling a medical need for an animal when its health is threatened.

    For example, equine practitioners have inquired about the legality of treating horses with Previcox®(firocoxib), a nonsteroidal anti-inflammatory drug labeled for use in dogs, instead of Equioxx®, which contains the same ingredient but is labeled for use in horses. There can be a significant cost difference between the two products, which is the cause of the debate. According to AMDUCA, however, because Equioxx® is labeled for use in horses, the canine product cannot legally be used in an extralabel fashion in horses. Selecting a canine product over an equine product for any nonmedical reason, including economics, is not acceptable. Some clients or veterinarians asked if economic concerns are a valid reason to use or prescribe a drug in an extralabel manner—this is true only in that a veterinarian can select an approved human drug to relieve pain and suffering in a non-food producing animal even when an identical approved animal drug is available.”

    Also from the FDA website themselves, they say: “In companion (non-food-producing) animals, you can prescribe an approved human drug for an extra-label use even if an approved animal drug is available.”

    HOWEVER. (You knew there was one coming, right?)
    Compounding drugs throws a wrench into it.
    The guidelines for prescribing ELDU for a compounding drug are here:

    The major point made is: “There is no approved new animal or approved new human drug that, when used as labeled or in conformity with criteria established in this part, will, in the available dosage form and concentration, appropriately treat the condition diagnosed. Compounding from a human drug for use in food-producing animals will not be permitted if an approved animal drug can be used for the compounding;”

    Dosage and form are going to be the issue here – if you can say Tristan needs something other than the dosage and form that Prascend offers (not pill or 1.05mg or whatever), then you are perfectly legal in having an rx for compounded Peroglide vs using Prascend.

    The big sticking point is going to be dosage – if Prascend is available in a 1mg tablet, you can’t compound it in a 1mg dosage – BUT it’s legal to compound it in 1.05mg or 3mg, etc. So as Tristan’s needs increase, this may become an option again.

    So long as the Pergolide is human and not a different veterinary species, you should be fine here (dosage dependent). Of course, at the end of the day, you can only do what your vet is willing to write, however I know other vets who would be happy to refer you to someone else who might write it if they were uncomfortable with the ELDU.

    Annnnddd essay over! Thanks for a fun lunch break for some of us over here! Gotta love working with 9832754328 vets.


    1. That was really interesting to read, and thank you so much for taking the time to ask everyone and write it all out! It seems like a lot of see sawing of “not allowed except when” to try and give leeway but mostly not allow it. Really interesting how they keep trying to leave loopholes open. I love my vet and she’s done so much for me; I know that if she felt that she personally had any wiggle room she would keep scripting out the compounded pergolide, but she cannot. For now, it sucks to pay more but I can manage it. If that changes I may seek her blessing to get a prescription elsewhere.

      Liked by 1 person

  2. It’s the same with omeperazole for ulcers! So frustrating… But I’m the same way, they get what they need.


    1. I was intrigued by your question and did some research. According to the FDA, because there is no new ingredient – it’s simply a way of packaging a long-used ingredient – the exclusivity expired in 2016:

      The bigger question for those of us hoping it will get cheaper is whether another company will pick up the ball and start making a generic version of Prascend. I don’t have any way of knowing whether someone will do that.


      1. Yes – it seems to have expired already because it’s a reformulation of an existing drug. The challenge now is seeing whether another company will take up making it. We’ll have to see.


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