That wasn't really that, and unfortunately, that doesn't have a simple diagnosis, treatment plan, or recovery phase. The reason there is so much contention over the appropriate treatment of PPID is because there's a lot the medical establishment doesn't know. And even more so for horses in the earliest stages of the disease; horses like Speedy.
Several things jumped out at me. First, it is not necessarily easy to interpret the ACTH levels. To simplify things, the ACTH level indicates whether things are under control or not. A "normal" range is somewhere between 9 - 35. One problem with checking the ACTH level is that it can rise from a variety of factors, none of which mean that a horse even has PPID. Stress, whether from trailering, pain, or even seeing the vet, is enough to rocket up the ACTH level.
The time of year the test is given can also raise the levels. There is a well documented seasonal rise in all horses. From late summer, around August, all the way through to the end of December, all horses will experience a rise in their ACTH levels. Scientists don't exactly know why, but the reasoning is that it helps horses prepare for winter.
The second thing I spent a lot of time researching was the dosage. The manufacturer recommends dosing by weight. In addition, the recommended maximum dose is 2 pills per day. While there are horses being treated with 5 - 10 or even more pills per day to control their symptoms, there is currently no published research using doses higher than 5 mg for a 1,000 pound horse.
Regarding the appropriate dosage, it should be noted that there is no cure for PPID. Prascend won't cure a horse; all it can do is control the symptoms. Even then there is no guarantee that Prascend will control them. That's why PPID horses still suffer laminitic events and ultimately death.
From the Laminitis Site, "PPID is a progressive disease, and the amount of Pergolide required to control the symptoms is likely to increase as the horse ages. Some horses only need Pergolide during the seasonal rise in the early stages of the disease. Many horses need an increased dose of Pergolide during the seasonal rise."
Dr. Tolley had three possible explanation for why Speedy's ACTH levels could have risen so dramatically while being treated with Prascend and showing no other clinical signs. A horse with levels like Speedy's should have shown something else to indicate the disease. First, Dr. Tolley posited that Speedy might not be getting the dose.
Speedy isn't the first PPID horse she's managed. Her own mare, Lilly, had PPID for more than 6 years before succumbing to laminitis. The ranch owner is an old hand at effectively delivering the pill. Dr. Tolley agreed that Speedy is more than likely getting his dose.
The second reason that Speedy's ACTH levels might have risen could be due to a "false positive". It is very possible that when Speedy's blood was drawn, he was under a high degree of stress, which we know raises ACTH levels. He had traveled nearly 40 minutes in the trailer, he was worried about Izzy's whereabouts, he was still dealing with a draining abscess, and he was facing the man who always sticks him with needles.
The third reason Speedy's ACTH levels might have risen is that his PPID symptoms are unaffected by the 1 mg. dose. This is a worst case scenario as it would suggest that his symptoms might not be controlled by Prascend. For now, we're going to assume his ACTH levels were high due to stress.
Dr. Tolley has never resented my questions. He's never been offended when I've asked for a second opinion or when I've consulted a different medical professional. And in this instance, his response was the same; do more research, ask more questions, consult other doctors. He welcomed my perseverance and thanked me for really thinking about how to approach this disease.
Based on that blood draw, we will either maintain the current dose or return to the 1 mg dose. We also have it in mind that we may need to raise the dose in anticipation of the seasonal rise in Speedy's ACTH levels. To determine that, we may need to do another blood draw in August.
When I pressed him for next steps, I was again met with his reluctance to answer. It was only when I finally explained that I wasn't searching for a miracle that he quit evading my question. Over the phone I could hear him give a sigh of relief. Essentially, we're already doing everything we can. That was his answer. We'll do bloodwork. We'll adjust his Prascend up and down. And we'll pray. I can do that.
And life goes on.