Phenobarbital side effects--how long?

[jtrosen]

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.

[tonyb286]

Hi. As far as I know, there are no known side effects or reports of dogs with such a compulsion following treatment with Keppra. However, I am very doubtful this is a compulsion, in the strictest sense of the term. Keppra is an unusual anti-seizure drug, and has no comparison to other epilepsy treatments. Being on both Phenobarbital and Keppra, it is very likely your best friend has an acidic-reflux problem, which may or may not improve as time goes on. The drugs are probably causing this - but it can be treated with a suitable antacid designed for canines. Raise it with your vet and ask for some antacid treatment that is safe to be combined with the other medications. Tony

[Jandandy]

I have a 5 year old beagle mix who had his first seizure in June.  At that time he was put on a low dose of PB and was fine until the end of August when he had multiple seizures and had to be hospitalized for 2 nights.  Now on PB 2x day and Keppra 250 mg 3x a day.  All was fine, no seizures but now has developed a compulsion to eat grass, leaves, dirt, twigs and then throws up.  Did this behavior over the last 3 days.  Now I can't take him out and I know you shouldn't feed a dog after they have thrown up.  He had eaten grass before but this is really extreme.  I think it's the keppra.  Will call the vet, but wondering if anyone else has heard of this side effect.

[tonyb286]

Hi. I empathise with you completely. I am an ex-nurse (following a career change and now retired), and despite knowledge and experience in dealing with various human ailments, I fall to pieces when it's 'one of my own'. For whatever reason, probably stress and anxiety, it is sometimes hard to look beyond dealing just with the symptoms.

I know the costs are enormous. We always want to do everything possible to help our best friends, and sometimes despite so much wanting to, we simply can't. I think your vet is right, there will come a day when Phenobarbital is likely to become necessary - and that might be sooner rather than later - but just take each day at a time. Tony

[Judy2dogs]

Thanks again.  Just got back from vet. He says she is on the pred 7.5 indefinitely. Went armed with questions, thanks to your input. He expects that at some point may have to add PB if seizures become more frequent & severe. I work in health care field and have dealt with human seizures without difficulty, but seeing one of your 'kids' in a full blown seizure is more than painful. Reading on this blog shows how much we are involved with our pets and wanting to take any discomfort away from them...much like parents of real kids.
Interestingly, an initial exam with neuro is $300, the MRI will cost $1700, and on!!!! Haven't made that decision yet...

[tonyb286]

Hi. I think the biggest advantage of a neuro examination is that you will get more accurate information and potentially a more accurate diagnosis. The huge problem with a brain tumor diagnosis (without any specialist involvement)  is it's somewhat guesswork on your vet's part - he is simply looking at the symptoms and making a judgement based on the symptoms alone. A neuro vet will have more knowledge and more experience and (even without surgery or scans) he will be able to make a more certain diagnosis. Without the diagnosis, you and your vet are 'hoping for the best' by what you are doing. It's a really difficult judgement - and costs are an enormous factor.

If it is a brain tumor, then there really isn't an 'average' time limit to when things will deteriorate. All dogs are different. The best way of thinking is to take each day as it comes and manage/treat symptoms as they occur. Keep a diary of events and observations, as this will provide useful info to your vet. The potential, with treatment, is to gain years of good quality of life - without any treatment, things will deteriorate rapidly.

Hope this helps.

Tony

[tonyb286]

Hi. You will be pleased to hear that the answer is NO, these symptoms will gradually disappear within 2 to 4 weeks. It's heartbreaking to have a dog with the side effects of pheno, but it DOES pass, so stick with it. And it is much more important to get the seizures under control than to withhold pheno and have no side effects. Have you got your next vet appointment booked for bloodwork to be done? This should be undertaken 2 weeks from the first day the phenobarbital started.

Also, make sure you keep a diary over the next two weeks of all side effects, any seizures, and the time of day you give the phenobarbital and how much is given. This info will be useful to you and your vet. Finally, make sure you give the phenobarbital at the same time every day and don't miss any doses.

Tony