Category:

Drugs

10/15/2020

US Equestrian has a fairly comprehensive guide that outlines which drugs are permitted and which drugs are not. Even so, some questions don't have a definitive, ready-to-go answer. Case in point, prednisolone.

Izzy was recently prescribed prednisolone for his Seasonal Recurrent Dermatitis (SSRD) which is being caused by midges. My vet reminded me to check out the withdrawal time with my dressage governing body, US Equestrian. While I was in his office, we quickly found the 2020 USEF Guidelines for Drugs and Medications. We located the Common Prohibited Substances page and quickly scrolled through the list. Prednisolone was not on either list (permitted with MRF and no MRF accepted). I assured him that I would dig more deeply.

Knowing that a steroid had to be on some list somewhere, I later started flipping through the pages, reading a bit more closely. On page 8 of the 2020 guide, page 12 of the 2019 guide, there is a list that details how long drugs remain detectable. Prednisolone is not on the list, but methylprednisolone is, and it's detectable for 14 days. That got me worried.

I spent a fair amount of time asking Google to describe the differences between methylprednisolone and prednisolone. The only results I got were for methylprednisolone and prednisone. I called my vet back. He assured me that methylprednisolone and prednisolone are indeed two different medications. Methylprednisolone is much more powerful and acts more quickly. Prednisolone falls under the category of "corticosteroids other than methylprednisolone and isoflupredone, e.g. triamcinolone and betamethasone."

NOT methylprednisolone.

The issue for Izzy is how long the drug is detectable. We have a show in less than two weeks. We have another show two weeks after that. Since the detectable time for methylprednisolone is two weeks, he wouldn't have been able to have a dose for a full month. That would not have been good.

Fortunately, the detectable time for other corticosteroids like prednisolone is seven days. This means we can't follow my vet's initial treatment plan of two weeks of 20 tablets a day followed by two weeks of 18 tablets a day followed by ... you get the idea. Instead, he'll get his last dose on Friday. He'll be off the medication for a week for a two-day show October 24th and 25th. He'll then get another week of the prednisolone, and then he'll go off it for another week so that we can go to another two-day show November 7th and 8th. He'll then go back on the prednisolone until November 30th.

His skin is finally not itchy , and it's nearly healed over.

Fortunately, Izzy has had enough medication - IV, oral, and topical, that his skin has finally healed over, and he is no longer itchy. Of course our cool evenings have probably helped nearly as much as the drugs. Our lows have been in the 50s which has no doubt annoyed the midges. I just hope that being off the prednisolone for a week won't allow the little boogers to gain a new foothold.

Fingers crossed!

Izzy's Skin

10/8/2020

It's tough to be so well loved, especially when it's by a gnat. Or midges. Or no-see-ums. Officially they're called Ceratopogonidae, and they think Izzy is a buffet of yumminess. Poor Guy. According to Wikipedia, there are more than 5,000 species of the little buggers, and they cover the planet from south of the arctic to north of Antarctica. Their bites are painful and can cause intensely itchy lesions. Izzy will vouch for that last bit.

Stuff I wish I didn't know.

Last summer, Izzy rubbed out a bit of his tail and nearly all of his mane. I knew he was itchy, but with fly spray and frequent showers, he made it through the buggy season with his skin pretty well intact. This year, he's been a hot mess. I've tried no less than a dozen products, many of which claim to be cure-alls for Seasonal Recurrent Dermatitis (SSRD), colloquially known as both summer itch and sweet itch. In short, the itchiness is a medical condition in horses caused by an allergic response to the bites of midges. Or as I like to call them, little bastards.

A photo from August.

When I took Izzy to see Dr. Tolley for his fall vaccinations, we formulated a plan to deal with the itchy skin medically instead of just topically. I've already mentioned this, but Dr. Tolley gave Izzy a shot of dexamethasone, a steroid that treats inflammation. I also took home a jar of Triamcinolone acetonide, another corticosteroid used topically to treat various skin conditions. On Monday, I drove back out to pick up a bottle of prednisolone tablets, a corticosteroid that decreases inflammatory or immune responses.

From Saturday.

None of these drugs are particularly cheap, especially the prednisolone. In fact when I calculated the cost of Izzy's new allergy pills, I gulped in dismay. A bottle of 500 pills costs $115 which sounds really cheap until you consider how many pills a day he'll be getting. Here's Dr. Tolley's plan beginning on Monday going through December 1:

20 pills a day for two weeks.
20 pills every other day for two weeks.
18 pills every other day for two weeks.
16 pills every other day for two weeks.

At the end of eight weeks, which is what this plan covers, we'll be right at November 30th. I only have 500 pills, but this plan calls for 658 pills which means I'll need to go grab another bottle. Each pill comes in at $0.23, so to cover the entire eight weeks, I'll spend $151.34. That's doable, and I've certainly spent a lot more on other things.

Next spring is when I'll start to feel the pinch. By then, we hope to start him on 16 pills every other day from April 1 though December 1. That works out to approximately 240 a pills a month ($55) for eight months ($441). I need a new envelope.

I wish they put more in a bottle.

The good news is that one of the steroids Dr. Tolley gave is working. Or more likely, some combination of two of them is giving Izzy some relief. Last night, all of his itchy spots were smooth with no raw skin showing. His forehead looked nearly healed, and his shoulders had new hair coming in. I wish I had thought to take a picture because he's nearly black now. His yellow coat has quickly been replaced by his black winter coat. That, too, usually fades by February, but for the month of November, he's normally quite dark.

I know he will feel so much better after just a few more days, and the cool weekend that's in store will help even more. I wish they made a Zyrtec or Claritin for horses where one pill a night did the trick. Fortunately, the pills dissolve completely in his beat pulp, and he wolfs them down without batting an eye.

Now I need to start shopping the online pharmacies to see if I can knock a few dollars off each bottle. Every little bit helps.

Vaccinations and More

10/6/2020

Izzy went to the vet on Saturday, and I think it was the first time he has gone by himself. He was a very good boy. Oh, and lest anyone worry, it was just a routine visit. Since we're doing at least two shows this fall, Izzy needed his Flu and Rhino vaccinations in order to satisfy US Equestrian's within six months rule.

Not what he had planned to be doing on Saturday afternoon.

When I made the appointment, I stressed that it was just for the vaccine - I hate to take up Dr. Tolley's time unnecessarily. I knew that if Dr. Tolley had time, he would give Izzy a thorough exam anyway; he always does. When I backed Izzy off the trailer, I asked Dr. Tolley if I could take Izzy over to the scale before he gave him the vaccine. Izzy clocked in at a light 1,260 pounds; he's been heavier. Dr. Tolley suggested we try and shove more food into him. I've since had that conversation with the ranch owner as well as doubled Izzy's rice bran to three pounds per day (along with his daily two to three pounds of beet pulp and full cup of milled flaxseed).

Full body check.

As we exited the scale, Dr. Tolley led us inside. I was a little surprised he put Izzy in the stocks as he was just getting a single vaccination, something Dr. Tolley usually does at the trailer. And then I realized that Dr. Tolley didn't have a line of patients, so we were his entertainment for the day. The truth is that Dr. Tolley is just so conscientious that he wouldn't feel as though he were doing his job if he just stuck in a needle and sent us on our way. If he gets the chance to put his hands on one of his patients, he wants to make certain they're in good health even if he's just seeing them for a quick vaccination.

Dr. Tolley used a piece of clear tape to check for pinworms.

Since Dr. Tolley asked how things were going, I told him about Izzy's skin condition. I ran through the list of all of the fly sprays and topical treatments I've tried over the summer, including the switch from flaxseed oil to milled flaxseed. Dr. Tolley agreed that treating Izzy from the outside was not working. Before prescribing anything, Dr. Tolley asked about Izzy's deworming cycle.

Both of my boys get fecal EPG tests done twice a year - in fact I had brought two fresh samples with me, followed by a tube of ivermectin each spring and fall. Dr. Tolley pointed out that pinworms don't show up on eggs per gram tests, so he did something I've never seen. He took a piece of scotch tape and pushed it gently into Izzy's bum and then adhered it to a blank slide. He slid the freshly prepared slide under the microscope and gave it a look. Fortunately he couldn't find evidence of pinworms, so the tail itching was attributed to the gnats that are eating Izzy alive.

You can just see Izzy's and Speedy's poop samples to the right of Dr. Tolley's elbow.

Since topicals aren't giving Izzy any relief, a steroidal plan was in order. He gave Izzy an IV injection of dexamethasone, a steroid that treats inflammation, and recommended prednisolone, a corticosteroid that decreases inflammatory or immune responses. Unfortunately, the prednisolone was out of stock and only arrived yesterday. I'll run back out there and pick it up. today. We'll start Izzy on 20 tablets a day, reducing it over time until we see which dosage is effective. The plan will be to give it until December 1, the end of our fly/bug season, and resume it by April 1 of next spring.

Examining Izzy's skin.

In the meantime, he also prescribed another topical cream, Triamcinolone acetonide, another corticosteroid used topically to treat various skin conditions. Hopefully this one works a little better than all of the other over the counter products I've tried.

Just some of the products I've tried this summer.

Even though I took Izzy to Bakersfield Large Animal Hospital for just a vaccine, I walked away having learned just a little bit more about equine health. Sometimes I feel like I need to add a little bit extra to my bill for the lessons that I get from Dr. Tolley.

Just kidding; my vet bills are high enough!

A Goopy Eye

10/5/2020

Every now and again, Speedy gets a goopy eye. Fortunately, I haven't had to take him to the vet for it. Years ago, my Arabian Mickey Dee got an eye infection that blew up overnight. His eye was covered in nasty green goop that looked like it came from a science experiment gone horribly wrong. I scrubbed it clean, and when it looked worse the next day, I hauled him down to the vet and left him for a few days so that my vet could treat it several times a day. Speedy's isn't anything like that.

Mickey Dee

Over the weekend, Speedy's eye got a little swollen with a tiny bit of goop. I am sort of prone to eye infections myself, so I know that quick treatment is the best way to ensure that it doesn't get progressively worse. In Speedy's case, I always clean the affected eye with a wet cloth, and then I irrigate it with saline solution.

My eye treatment kit: clean container, small syringe, saline solution

Speedy's not a fan of the treatment, but he also doesn't resist too terribly, at least, not for long. Not many horses, nor people, will stand quietly while you flush their eye out. To do Speedy's eye, I have to bend his head around so that he's staring at his shoulder. At first, he flies backward, certain it's going to hurt. i just go with him, telling him it's okay. Once he stops, I pinch his nose a bit and rest the syringe in the corner of the eye. For the first squirt of saline, he usually jumps backward until he realizes it's not acid.

Pre-treatment

When he finally accepts the treatment, I can push the syringe underneath his eyelid - by this point he has his eye squeezed tightly shut. I think it must feel good, because once I start depressing the plunger, he stands pretty quietly. Or, as quietly as one can with liquid being shot into your eye. I wouldn't be able to stand still for long either.

Not my actual syringe, but you get the idea.

I usually flush it at least three times with a 20mL syringe, using all 20 mL in each flush. In between flushes, I always give Speedy lots of pats and cookies. You would think he would associate the cookies with getting his eye poked, but so far, he feels the cookies are his due payment for the pain and suffering I've caused him.

I am hopeful that by this afternoon the goop is gone and his eye is back to normal. If not I'll treat it for a few more days. If it's still not better, I'll give my vet a call, and then I'll need to order a new bottle of saline. Better to have too much on hand than not enough!

So "Izzy" or Isn't He?

8/26/2020

A week or so ago I wrote about Izzy's dramatically changing coat color. In that post I posited that he might have the cream dilution gene. Several people wrote to me privately expressing their doubts about that theory. Instead of a genetic cause, it was suggested, and not for the first time, that Izzy might have some mineral deficiencies, specifically copper and zinc. So it seems that there are three possible explanations.

From this color in April ...

First, it just might be how he is. He's dark in the winter and fades in the summer. Gray horses undergo coat color changes all the time. What do they say about Occam's razor? The simplest explanation is most likely the right one. But not always.

Second, he might have the cream dilution gene. In Izzy's pedigree, neither the Thoroughbred side nor the Oldenburg/Anglo-Arabian side recognize the color "buckskin." Instead, the Jockey Club recognizes Thoroughbreds as being either bay, black, chestnut, dark bay/brown, gray/roan, palomino (which carries two copies of the cream gene) or white. The Oldenburg Registry of North America recognizes brown, black, chestnut, gray, and bay horses. My research, limited as it was, says that on a black or dark bay/brown horse, the cream dilution gene can produce a buckskin, a sooty black, or simply a lighter brown horse with black points. In other words, without a genetic test, you can't tell just by "looking."

To this color in August.

That leaves the third option; Izzy might have a copper and zinc deficiency. Again, my research consisted of skimming articles found by doing a Google search. What I saw was that zinc deficiencies are rare. Over consumption on the other hand can decrease copper absorption. Some of the processes that copper is required for are energy production, iron metabolism, connective tissue formation, central nervous system function, and melanin production. Coat color is determined by the presence and proportion of melanin pigments.

Most of the articles I read warned against supplementing just with copper and zinc as that combination can negatively interact with other minerals in the body. Instead, it was recommended that horses with suspected copper and zinc deficiencies be fed a commercially fortified feed or a good mineral supplement. I've done both (Platinum Performance and Horse Guard) over the years for long stretches of time, but Izzy's coat still changes colors. He either doesn't have a zinc and copper deficiency, or, the supplements weren't enough to overcome the deficiency.

Izzy's Genetic Test

I am not worried about a copper and zinc deficiency, and it doesn't matter whether Izzy does or doesn't have the cream dilution gene, but I decided to find out for sure. UC Davis has a Veterinary Genetics Lab that is "open" to the public. They offer a long list of genetic tests, most of which seemed quite cheap. You can check for just about anything. For $25, I will know definitively if Izzy has the cream dilution gene or not.

Earlier this week, I pulled the requisite mane hairs, ensuring that the root bulbs were attached. I taped them to the form as directed and dropped the whole thing in Monday's mail. The results should be back in a week or two. Either way, I know I should put both horses back on the Horse Guard Vitamin and Mineral Supplement. It won't hurt, and it probably helps their overall health.

Every time I try to keep things simple, I add in yet another thing.

<<Previous

Not-So-Speedy Dressage

Drugs

Izzy's Skin

Vaccinations and More

A Goopy Eye

So "Izzy" or Isn't He?

About the Writer and Rider

About Speedy G

About Izzy

National Awards

Stuff I Read

By Topic

Archives