Warning re allergic reaction to Penicillin

Armas

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I have cut and pasted this from a French forum, as I think its an important piece of information for any horse owner and the owner of the horse wanted to warn people.


Yesterday I had one of the worst days of my life.
I came home after being out for the afternoon and went to see Bentley, my big horse who was banging his stable door. I found him trembling all over and breathing very fast and coughing. I took his temperature which was 38 degrees and then I rang the vet and described what was happening and he said he thought he had been stung by something and told me to give him two bute and he would be fine in an hour. I rang my friend who advised me to check his mouth for stings or obstructions and when I did I could see his tongue and gums were blue. I tried to get him to eat the bute but the coughing was worse and he couldn't eat. I rang the vet back and told him to come NOW.

I brought him out of the stable and tied him outside and I thought he was going to die right in front of me as he couldnt get his breath and was just coughing and coughing and his tongue was going more and more blue.
The vet arrived and immediately said that Bentley was having an asthma attack and he had no lung sounds on the right hand side. He also had a temperature which had gone up almost 1 degree since I had phoned the vet. The vet gave him a huge injection of an anti biotic and then almost immediately he had a massive allergic reaction to it. He went rigid and then threw himself over backwards. He got up and then threw himself the other way.
He landed on our metal gates and then on a pile of roof tiles smashing them to bits.

He then went absolutely mental and I had to let him go and he galloped off to the field. He jumped the hedge which is well over 5' into the field and then galloped around for about 20 minutes. Unfortunately for me he is supposed to be halfway through 6 weeks box rest.

Eventually we were able to catch him and bring him back in and the vet was able to inject the drugs to help him breath.

He has said that there is something in our barn where the stables are that has caused the asthma and that Bentley must not go back in there.

I am still in major shock and have a terrible rope burn to my left hand. Bentley is turned out and being checked every hour.

On Monday the vet is coming to take blood tests to see what his white blood cell count is.
He had also burst a blood vessel or something and was pouring frothy blood out of his nose.

This morning he seems ok. He is battered and bruised (as am I) but his temperature is normal and he is only coughing occasionally. His cuts and grazes have been slathered in sudocreme to keep the flies off. He actually trotted up to the gate to see me. He looks sound so that is a blessing after the gallop he had.

He has to stay out which is a b****r because the flies are bad. I have put a fly rug on and a fly mask but the rug is a bit small on him. I sprayed the rug with fly spray but it made him cough so I can't spray him. I have given him haylage to eat because we have no grass and I dont want to give him hay just in case that sets him off again.

The vet left me with a syringe of Cortisone just in case he should have another asthma attack.

Apparently reacting to Penicillin injections is not rare and I am telling this story here to warn people. Here is a short passage explaining what happened that we found on the internet.
Penicillin is very commonly administered to horses in a formulation known as penicillin procaine G. The procaine is a local anesthetic, related to lidocaine, novacaine and cocaine! It helps to give the formulation a long-acting effect, so that it can be administered only twice a day. When correctly injected into the horse's muscle, it causes no problem. However, if the formulation is accidentally injected into the horse's bloodstream, the procaine goes to the horse's brain and triggers a spectacular reaction (imagine a horse getting a "hit" of cocaine). Most horses begin to tremble violently and throw themselves over backwards. There is no antidote when this occurs and an affected horse will recover in just a few minutes as long as it doesn't damage its skull or spine. Obviously, this reaction can be very dangerous for bystanders.

The only thing that was different yesterday from any other day was that we opened a new bale of hay but it was from our normal supplier so God knows what caused the asthma attack.
 
I have a horse who is allegic to penicillin.
His neck & face swelled up & he had difficulty breathing. Absolutely dripped with sweat & started tharashing around. vet was luckily still there & was able to give him relaxants & cortisone. it happened within 10 minutes of penicillin being injected.
But he is only 1 horse out of over a hundred I have had to deal with.

It's benefits far outway the very few it harms.
 
It's not always that the horse is allergic to the penecillin that it goes crackers. It's because it has accidentaly been put into the blood stream but most vets won't admit that they have cocked up.

I've held horses that have had this happen to them and it's not pleasant but is over within minutes.
 
It's not always that the horse is allergic to the penecillin that it goes crackers. It's because it has accidentaly been put into the blood stream but most vets won't admit that they have cocked up.

Speaking from personal experience, as well as the published research (case series of 54 PPG reactions) then it is most often not because a vet "cocked up", but because of an idiosyncratic reaction to the procaine portion of the injection. Certainly when it happened to me I can 100% guarantee it was not in a blood vessel.

It is doubtless a scary reaction to see, but almost invariably has no long term effects, and shouldn't put people off an extremely useful (and cheap!) drug.
 
My tiny rescued miniature shetland had a similar experience. He was very weak and malnourished and then on top of this he had a colic attack, long story. The vets were wonderful and after his symptoms settled a little they injected him with Fynadine. It should have gone into a vein but it was dark and he was so very tiny, no flesh at all and long hair, that it accidentally went straight into the carotid artery and straight to his brain. The instant he was given it he reared straight up and over backwards. Thank god he's so tiny so he didn't hurt anyone or himself. Vets were totally honest about it and said they'd seen the same thing happen only once before with a big cob. It's terrifying. Thank god, my mini was ok and the colic was resolved and he slept like a baby for the rest of the night.
 
It's not always that the horse is allergic to the penecillin that it goes crackers. It's because it has accidentaly been put into the blood stream but most vets won't admit that they have cocked up.

I've held horses that have had this happen to them and it's not pleasant but is over within minutes.

its not a case of 'cocking up', the horse only has to tense its muscles and a vein can move causing the drug or part of the dose to be injected into it!
ideally all injections (especially large doses) should be given in an enclosed area.

every drug has the potential to cause an allergic reaction, but not sure if yours sounds like an allergic reaction but more like a'direct hit' into the vein.

i would be counting my blessings sounds like no long term harm has been done and you have been lucky
 
Its a reaction to the procain, not the penicillin itself and is a rare but well documented event. I know of a horse which took off around the field and ran straight into a tree. I'm often asked to give penicillin injections to other peoples' horses because they don't want to and I always ask if the horse has had penicillin before. If it hasn't I politely refuse. It is important that you draw back on the syringe once the needle is in to check for blood which would mean you have hit a vein and must start again.
 
Just to add to this as my mare is allergic to penicillin/pen strep.

had the vet out as she had a very inflamed leg and colicing due tot he fact she was having trouble going to the toilet because she stands right out to do both and couldnt due to leg.

she had injections to help with colic, and also pain relief for leg, and the pen strep for leg infection.

After a day or to she started to emit a very strong smell which was initalliy believed to be the infection breaking out from her leg, but a day later the only way to describe the smell was that of dead/rotting flesh! When mucking her box out the smell became stronger so it was evident that the smell was coming from inside her and was passing out in her faeces.

Vet was immediately called (same vet that treated her above so new what she was being given) he arrived and took temps breathing rate etc, examined faeces, he then said she was having a reaction to the pen strep and it was killing her gut lining, and had we not called them/ stopped giving her pen strep she would of been dead with in a few days and it would of killed more of her gut which would of the ruptured and killed her.

We then had to administer different antibiotics along with syringing a mixture of water charcoal pepdibismol electrolytes and yoghurt into her as often as possible to help her gut to heal.
She was also highly infectious to others due to the bacteria in her feaces and had to be completely quarantined and all the mcuk from her stable burnt to kill of said bacteria.

she had about two weeks of antib's and charcoal, and for her not to be infectious to others, although the smell albeit not as potent remaind for a good few months, and even after that when a change from hay to haylage or back again occured, the smell would become apparent. But now finally after 18 months we no longer have the smell at all.

It is now on all records that she is not to have it under any circumstances as it could of been a whole different out come.

sorry its so long :)
 
One of ours is allergic to penicillin - we'd had him for 14 years before we found out - ie he was ill enough to need it! It was like he was hungover for about 3 days, spent a lot of time lying down, and was very quiet. He did get over it though, and was back to normal quite quickly :)
 
This is interesting to read as I had the vet out today for my boy. He is having a strong allergic reaction to fly, midges or something and his legs have swollen and are weeping. The vet decided against injecting him with penicillin because she saw how he reacted once to Buscopan and she was worried he seems very sensitive. She deiced it would be safer to do the penicillin in a topical cream instead. Having read this thread I'm glad she did.
 
Horses can be allergic to penicillin but i think the post that started this is a classic example of catching a blood vessel. The running blind part of the reaction is what causes the most problems in most cases!
 
The owner has clarified in the original thread on the other post that the horse was not allergic to penicillin. He was having a weird reaction, possibly a severe reaction to something else which they have yet to identify, possibly also an infection (rising temperature) so he was given the penicillin for that. The reaction is believed to have been down to the procaine, and is a known, very severe but rare side-effect.
 
It was my horse that reacted to the Penicillin injection and we are pretty sure that he had a reaction to the Procaine. The vet did drawback to ensure that he had not hit a vein but it only needs to be the tiniest capilliary that gets nicked for this reaction to happen.

One thing I would like to clarify is that this reaction was not over in minutes as someone has stated. My horse had a very severe reaction which resulted a horse on box rest for a DDFT injury galloping flat out round the field for at least 5 minutes and probably more and then taking another 15 minutes to catch and bring under control. This because we brought him out of the stable due to his breathing difficultly which we now think was due to being stung by something.

I also feel that my horse has not returned to normal nearly 3 weeks after the event. He was a rock steady and reliable horse who never ever put a foot out of place. He has lost all his confidence and is now very panicky and has an odd look from time to time in his eye.

I think it is going to take a few more weeks for him to get over all this. I am devastated by the whole thing and as for the DDFT injury... Lets just say that we wont be going back for the planned rescan next week as he is once again very lame.

By the way Armas seeing as you have cut and pasted my whole thread about this it would have been nice if you could have asked me if it was ok or at least told me you were going to do it.
 
It was my horse that reacted to the Penicillin injection and we are pretty sure that he had a reaction to the Procaine. The vet did drawback to ensure that he had not hit a vein but it only needs to be the tiniest capilliary that gets nicked for this reaction to happen.

One thing I would like to clarify is that this reaction was not over in minutes as someone has stated. My horse had a very severe reaction which resulted a horse on box rest for a DDFT injury galloping flat out round the field for at least 5 minutes and probably more and then taking another 15 minutes to catch and bring under control. This because we brought him out of the stable due to his breathing difficultly which we now think was due to being stung by something.

I also feel that my horse has not returned to normal nearly 3 weeks after the event. He was a rock steady and reliable horse who never ever put a foot out of place. He has lost all his confidence and is now very panicky and has an odd look from time to time in his eye.

I think it is going to take a few more weeks for him to get over all this. I am devastated by the whole thing and as for the DDFT injury... Lets just say that we wont be going back for the planned rescan next week as he is once again very lame.

By the way Armas seeing as you have cut and pasted my whole thread about this it would have been nice if you could have asked me if it was ok or at least told me you were going to do it.
You posted the information on a public forum you posted the information to warn people if you did not want it shared don't post on a forum.
I also stated at the top of the post "I have cut and pasted this from a French forum, as I think its an important piece of information for any horse owner and the owner of the horse wanted to warn people"
 
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Yes Armas 'I' posted it on a forum. You could have posted a link to that forum and the info or you could have reported the gist of it here. You copied and pasted every word I wrote.

As I said it would have been nice if you could have sent me a message on the other forum to tell me you were copying and pasting the whole of my thread to another place. I would have thought it was a polite thing to do.
 
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Yes Armas 'I' posted it on a forum. You could have posted a link to that forum and the info or you could have reported the gist of it here. You copied and pasted every word I wrote.

As I said it would have been nice if you could have sent me a message on the other forum to tell me you were copying and pasting the whole of my thread to another place. I would have thought it was a polite thing to do.

When you post something in a public place, you need to accept that that's just what it is, public.
 
Yes Lady La La you are right.
We think now that maybe the hay had Pine Processionary caterpillars baled up in it! This might have given my horse the awful coughing and asthma symptoms he had. He literally couldn't breath and was just going blue. We will never know now but it is something to bear in mind.
 
My gelding had a very similar reaction. The penicillin was injected by myself, something that I have done hundreds of times before without problem. I always draw back on the syringe first but this particular day I somehow still hit the blood stream, within about 60 seconds of administering the penicillin my horse was rearing over backwards and was like he had gone crazy. Scared the living daylights into me! I immediately rung my vet but within minutes it had passed. He remained 'quiet' for sometime but did fully recover.
I'm greatful for this thread as up until now I had not heard from anyone else it happened to and I am greatful to know that sometimes it just happens.
My vet had a good explanation... horses blood vessels do not follow a prefect map so if a horse moves a muscle a tiny amount you can hit a vessel and not know.
 
There was an article many years ago in Your Horse, or something about a girl who had a horse who had cut itself. The vet, the mother of this girl and this girl were in the horses stable and the vet injected it with penicillin. All of a sudden the vet shouted at them to get out of the stable and they all ran out. The horse had a massive allergic reaction to penicillin and threw itself around the stable. It broke its leg kicking out at the stable wall whilst floundering around. It has to be pts. The vet said that if the horse had been outside as was your horse, it would have recovered as it would have just ran around and not hurt itself (hopefully) on anything.

I would always ask my vet should my horse need penicillin if he could inject it outside in the field so that if possible I could let him go if he did have a reaction but I know its not a very practical and I only know this because of the article I read in the magazine years ago. I know the reaction is very rare but I myself am allergic to penicillin and had a bad reaction when I had my appendix out when I was six and my throat swelled. They had to give me tetracyline instead which can turn teeth yellow in children under the age of eight, luckily mine aren't too bad, and if it saves your life what the heck! Teeth whitenening wasn't around in 1976!!
 
Yes Armas 'I' posted it on a forum. You could have posted a link to that forum and the info or you could have reported the gist of it here. You copied and pasted every word I wrote.

As I said it would have been nice if you could have sent me a message on the other forum to tell me you were copying and pasting the whole of my thread to another place. I would have thought it was a polite thing to do.

It doesn't work like that. Once its on a public forum it becomes property of whomever wishes to use your words I'm afraid.

Like they say, if you don't want it shared/copied/stolen/borrowed, don't publish it in the first place. Armas is within her rights to do this, God knows I have done a similar thing enough in the past and make no bones about it either.
 
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