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Phenobarbital side effects--how long?

My dog (shepherd/husky mix, 73 pounds, 12 years old) began to have grand mal seizures last week. He had two seizures, one on Sunday and one on Monday, at almost exactly the same time in the evening. After the second seizure, the vet put him on phenobarbital (97 mg/2x per day).

He's been on it for five days now and is still pretty out of it. He is extremely lethargic (sleeps most of the day), has coordination problems, and weakness in his hind end. He walks veeery slowly. He's also extremely hungry and thirsty. I've read that all of these are possible phenobarbital side effects. How long do these usually last before the dog gets used to the medication? I'm hoping that these are not signs that something else is wrong, though I am aware of the possibilities.
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Avatar universal
hi,  new to the page BUT please stop the Rimadyl
all of those related drugs are biggies for liver kidney fails in older arthritic dogs
the exact ones they give them to
precvicox is THE worst Ive known too many aged dogs go down within a few days of using it.
other names vary but usually an X in it = for the  coX2 inhibitors
if you really must? meloxicam liquid is far gentler and you can usually halve the dosage and still get good relief
ONLY ever use them for a few days at most.

and if theyre on the phenobarb etc its a double whammy, liver assault wise

Ive used the injectable Pentosan aka cartrophen a series of 4 injections over a month they are  close to miraculous in the results of bad arthritis or joint issues. and safe.

and I am here because my 62kg great dane/staghound had his frst  seizure while asleep next to me on 26th dec 2016
then a follow up jan 31st
both during day in what i wouldnt have thought deep sleep cycle
the first one he was going blue due to tongue in throat
my idiocy  cost me one severely damaged finger and stitches and broken bone;-(
yeah tried to move his tongue
he came round as I did and chomp!
no one else Ive noticed mentions any aggression after attacks?
my fellas off kilter disoriented as you would be...but also scared and  likely to growl/snap for a while after.
with his size and weight and 3 others in our pack...its been..hmm.."interesting" shall i say?
today we started an 100mg phenobarb   1/2 2x a day
see how we go

the newest pill on market is supposed to have near no side effects BUT at a cost in AU$ or 170  a month , opposed to 40 for PB  its an option for the well off or small dog owners only really
http://www.ncbi.nlm.nih.gov/pubmed/26330063
brand name is PEXION
Helpful - 0
1916673 tn?1420233270
Hi. I think the slower movement is probably a mixture of age and the phenobarbital. At 12, he's entered old age. But on the plus side, it seems the pheno has done the job it's designed to do, which is great. As time goes on, there may be more seizures, so just look out for them - if it happens, the dose may need adjusting or you can add something like potassium bromide which will help boostr the effects of the pheno.

Tony
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Avatar universal
I just wanted to add my experience.  Reading this thread helped me through a rather scary period.

Duncan, Our 12-year-old yellow lab mix had his first grand mal seizure in September.  A horrific experience for my wife and I, who were totally unfamiliar with it.  Next day, we took him to our vet.  His opinion was that since this was the first time, let's take a "wait and see" approach.  Bring him back in if there is another seizure. They did some blood work which showed nothing unusual.  Two weeks later, he had his second seizure at 4am.  We called the vet when they opened at 8.  They said they had an opening at 11am and bring him in then.  At 9am, he had another seizure.  We called again, and they told us to bring him in RIGHT NOW.

Our vet prescribed Phenobarbital (8 mg, twice a day).  However, he felt that if Duncan had epilepsy, it should have shown up earlier in his life, probably by time he was five years old.  It certainly wasn't unheard of for epilepsy to show up this late, but he felt that a brain tumor was probably more likely.  He wanted to know if we'd seen anything unusual about his activity, primarily in motor skills.  Was he having trouble walking in a straight line?  Was he turning his head unusually?  Balance problems?  Anything at all unsymmetrical about his actions?  We hadn't seen anything.  He told us to keep him on the Phenobarbital and bring him back in in a month.

Like everyone else has seen, he was dopey and unsteady for that first week.  After than, his perky demeanor returned, but he was still a little wobbly in the back end.

After a month (and no further seizures), we brought him back in for more blood work, which came back normal.  Our vet felt that the 8 mg dosage didn't need to be adjusted.  Keep him on it and let them know if there were any further seizures or changes.

In December, we brought our dogs in for their yearly physicals.  Our vet said that the lack of any seizures since starting the medications was VERY promising, and if Duncan could make it a few more months, he'd feel confident saying that the problem IS epilepsy and not a brain tumor.

Even now, Duncan is very slightly unsteady on the back end.  He still runs full tilt and terrorizes all the local squirrels, but he doesn't bound up the stairs like he used to, and walks up them slowly and carefully.  Is this due to the medicine?  A permanent result of the seizures?  No idea.  But overall, we're very happy with the outcome.
Helpful - 0
1916673 tn?1420233270
Hi. I think there's a lot of room for optimism here, so yes, wait and see and write anything down that you think might be relevant so you have a record of what might have occurred and when. Phenobarbital does take some time to work its way out of the system, so there may still be some effects lingering, which of course could be keeping seizures at bay. If the seizures do return, at least you know what will help control them. In the meantime, I would urge you to try and get the vet to perform a blood pressure check when you go back for the next run of tests.

Tony
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Avatar universal
Hi Tony,

I did speak with the Dr. about the BUN and Creatnine levels after I found her original documents. When I first adopted Sugar her BUN levels were normal. I took her to the vet 2 weeks later for a teeth cleaning. This is when they noticed her BUN levels were in the 40s, never again were they abnormal. Our new vet believes that it could have easily been a dehydration situation or maybe she did't get enough to drink that morning. We are still investigating in Sugar's case, but as of now we are still seizure free (we have not had a seizure since we were on the phenobarbital) and we are now completely off of the phenobarbital. The barking I was originally concerned about has stopped. In fact, it stopped almost completely the day we lowered the pheno dose and she slept through the night completely. Now that we are off the pheno it has stopped completely. She is a completely different dog now. We will go back in for another check up and they are supposed to check everything out again. For now, it is a waiting and prayer game, but we are definitely keep an eye on everything!
Helpful - 0
1916673 tn?1420233270
When creatinine is high but BUN is normal, there is a suggestion of dehydration and/or heart issues. There is also the possibility of obstructed urine ducts. Temporary high creatinine can also be caused by a recent meal, so it's always best to check creatinine before the dog eats anything during the day of the test.

Depending on how the test is performed, high blood glucose, vitamin C supplements and certain antibiotics (cephalsporins, particularly) can falsely raise creatinine readings.

I think it's worth keeping an eye on things and having a repeat of all tests (and blood pressure) in a couple of months time, assuming Sugar stays seemingly well during this time.

Tony
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