Hypothetical question regarding phenylbutazone

We all know it’s not approved for human use because it can cause aplastic anemia, which is serious and can kill you. Was pulled from the market sometime in the 50s by the FDA.

With that in mind, how much would it take? I know when I give my horse bute, it’s that teeeeny little scoop for 1200 lbs of equine. Some of that powder gets on my hands and I’m sure some of it has gotten into my mouth before.

How much, exactly, would it take to actually poison or harm someone?

I’m not concerned about it as I don’t know nor have I heard of this ever being an issue, but as a hypothetical I wonder.

That’s a good question, as I, too, handle it daily and know I end up with it on/in me. I had no idea.

I think in humans, the efficacious dose for RA was about 300 mg/day…

I read that you should not get it on your skin. I had an elderly horse that got it daily and I am sure I did sometimes to no obvious bad effects. But I just kept a rubber glove to put on when I measured that out.

I was in pony club with someone who claimed to have eaten a gram a day for several months. It’s been almost 20 years and she seems healthy enough.

[QUOTE=Highflyer;8276100]
I was in pony club with someone who claimed to have eaten a gram a day for several months. It’s been almost 20 years and she seems healthy enough.[/QUOTE]

I suspect she’s suffering from faulty memory wrt the dose.

Bute is not easily absorbed through the skin. I wouldn’t think twice about getting a bit of powder or paste on myself. Inhaling it might be a bit of a different story with those mucous membranes. However…as I understand it, the real issue with bute is that in combination with other meds like acetaminophen, it can really hang up your liver.

Note that many of the wonderful drugs we use in veterinary medicine now were developed for human use originally but had serious side effects. Rimadyl comes to mind from “my day”. I used to have clients come in all jaundiced about 10 days in from their last script for the dog and say “oh, I dropped the bottle of pills down the toilet” etc…because Rimadyl was effective but caused problems in humans.

OP…I don’t have a precise answer for you. I surely wouldn’t take it–especially not in combination with other NSAIDs. But I don’t think that you need to be tremendously careful administering it either. I mean…have you ever looked at the MSDS for distilled water? EVERYTHING is dangerous. :wink:

Phenylbutazone-related blood dyscrasias are typically dose-related, and were associated with therapeutic use in humans, not so much from occasional exposure, as would be the case with administration of the drug to one’s animals.

a 2013 review in the Veterinary Journal concluded that phenylbutazone residue in horsemeat was at a sufficiently low levels so as not to constitute a public health risk. (haven’t got access to the entire article at present, should have it in a couple weeks)

At our vet hospital, there is a plaque on the wall honoring a vet tech who died of aplastic anemia. I have always wondered if her aplastic anemia was caused by handling Bute.

We don’t use Bute at my barn. We use Aleve, Previcox, or Banamine.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2465827/pdf/postmedj00397-0053.pdf

Interesting old article on Bute. They did not feel there was any relationship between the dose of Bute and aplastic anemia. If you are sensitive to Bute, it doesn’t take much to knock out your bone marrow and blood cells.

Interesting thread, I was not aware of this.
Often we handle all kinds of drugs without thinking really.

It would be good to know which of the common drugs we use on our horses could pose a risk to us, merely by handling. Is there such a list?

I remember squirting a tube of Dormosedan gel over my hands in the past, I wondered if I was going to get sleepy, but I was fine.
More recently with a needle shy horse I ended up with the contents of a WNV/EEE vaccine running over my hands, that got me a bit worried wondering what does or does not get absorbed thru the skin.

[QUOTE=AKB;8276834]
At our vet hospital, there is a plaque on the wall honoring a vet tech who died of aplastic anemia. I have always wondered if her aplastic anemia was caused by handling Bute.

We don’t use Bute at my barn. We use Aleve, Previcox, or Banamine.[/QUOTE]

I would bet it was from Chloramphenicol exposure. It goes on every bottle we prescribe to wear gloves as it can cause aplastic anemia in humans. It is absorbed through the skin. Chloramphenicol is no longer used in humans but is an excellent antibiotic for animals.

Species to species phamokinetics are different and can not always be assumed to be the same. What is harmful in one m be lifesaving in another.

I was prescribed bute in high school ( mid1970’s), in order to run hurdles on hot shin splints. By a doctor. It was very effective, and I experienced no negative side effects. It was encapsulated with a coating, looked like red smarties.

At racetracks, death from ingesting butazone meant for horses has been a known occurrence. Usually uneducated backstretch workers, who are injured and sore and don’t know any better. Liver and kidney problems I think is what kills them. Dosage too high, and not encapsulated, and kept on for a long period of time. Regular handling of bute being used for horses isn’t a health danger. It’s not like Rompun. Rompun WILL kill you if injected accidently into a human. Even handling a syringe that has some on the outside of the plastic, or pulling a needle cap off with your teeth can cause a reaction. A vet once told me that if you accidently stab yourself with a needle with rompun in it, you are to grab the bottle, so that when (IF) you get to hospital in time, they will know what drug you have in you, so that they can give you an antidote, and treat you effectively. Because by the time you get to hospital, you will be non responsive, with the bottle clasped in your fist.

[QUOTE=AKB;8276843]
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2465827/pdf/postmedj00397-0053.pdf

Interesting old article on Bute. They did not feel there was any relationship between the dose of Bute and aplastic anemia. If you are sensitive to Bute, it doesn’t take much to knock out your bone marrow and blood cells.[/QUOTE]
This is my understanding as well.
Don’t mess around with bute. Aplastic anemia is awful stuff!