Certain herding breeds of dogs have trouble with certain heartworm brands. I have heard (on another forum) of labs having issues with seizures, so don't know if that is a breed related problem. Something that you take monthly, that works like heartworm medicine, can't be too good for your dog. Especially if they have been taking it for over a decade. If it was my dog I would take it off of the heartworm and give it a couple of months. If he's on flea medicine I would also quit that for a while, unless you live in an area that is infested with fleas this time of year.

Sorry but I wouldn't spend $3000 for a test that is a maybe on a 14 year old dog. How much have they invested already? Not to be callous, but I would hate to see them get so in debt that they can't pay their bills.

Since the dog is still with us since starting the seizures in July, this might not be the problem, but *make* the vet check thyroid;
vets often try to diagnose something different, having been taught that hypo-thyroid disease is "rare"...
but it isn't.

The test isn't expensive, & the thyroid pills aren't expensive.

I wish you & your friend & her dog the best.

Thanks for the suggestions.

Has the vet considered that these may be hypoglycemic seizures? These are blood sugar-related, not classic brain-centered epilepsy. We had an old girl develop hypoglycemic seizures (likely caused by pancreatic cancer, but we did not care to invest time and money - or stress her - trying to pin-point a diagnosis). We were able to manage her for 3-4 additional months by feeding small meals every 4 hours (around the clock - she LOVED being woken up to eat :o) But it eventually catches up with you, and we put her down after a particularly devastating seizure. We let her sleep it off, and she had a couple of nice final days, but it was definitely time to let her go.

Housefairy, please don't make uninformed inferences. Heartworm prevention is a very safe medication, it stays in a dog's system for a maximum of 2 days and it prevents a DEADLY disease. Some breed dogs with MDR deficiency, which is generally NOT found in labs, can't take HIGH doses of ivermectin, but are completely OK with the low dose found in some brands of heartworm prevention. They can also safely take milbemycin, selamectin, and other preventions. Frontline flea control is not at all absorbed into a dog's system so that is also completely safe. It also prevents TICKS which transmit diseases that cause SEIZURES. There is absolutely no reason what so ever to discontinue these extremely important medications.

The fact that she's had "tests" is not very informative. I can think of a lot of tests that I would run in an older dog with seizures, including but not limited to:
complete exam with lesion localization
Phenobarbital level
CBC
chemistry profile
urinalysis
Bile acids profile
thyroid panel
tick born disease panel
CSF tap
chest radiographs
abdominal ultrasound

When deciding to run a test of any type one has to consider what treatment will change based on the results of the test. So let's say the MRI is completely normal- what do you do? What if it shows a brain tumor- will the friend treat it? Not too many hospitals can do definitive treatment on a brain tumor, maybe they can do chemo or radiation and make the dog more comfortable for a while but maybe not. Also the cost for these treatments can be high. Pretty much when a dog older than 7 starts having seizures, unless you can rule out tick born, hypoT4, or infectious causes you're going to end up with a brain tumor, which is what they are looking for with an MRI. I doubt I'd do it in this case because if my other non-invasive tests were negative it's most likely a brain tumor and I wouldn't treat it; I'd just try to make her more comfortable.

There are also other medications such as potassium bromide and gabapentin which can be added to phenobarbital to help prevent seizures. That assumes the proper dose is being given now, which you can tell only by testing the levels. At this point, if the other tests have been done and were negative, I'd try to stop the seizures and if I couldn't, I would let her go. That's just me. Some people just NEED to know what is wrong before letting their pets go and if they have the funds to do this, it's their business and their perogative, which is also a good choice. My only objection is to continue to allow seizures without relief. I would definitely feel 100% comfortable in recommending euthanasia for refractory seizures, and in fact have done so.

I'm really sorry that she is going through this. End of life decisions are very personal and I think most people make better decisions when they are given correct information and all of the options. It is up to the owner to decide what to do with the information, for the most part. If the vet feels the patient is suffering and the owner is in denial, that is a different situation. But it sounds like your friend is trying to relieve suffering while finding a diagnosis. As long as it doesn't go too long and they are still trying to control the symptoms (which I think could be better), and they are being realistic about what the most likely diagnosis is, then it's their choice to get an MRI or not.

Meghane, when I read the FDA approvals of heartworm medications it looks like they tested for six months before the necropsy. I couldn't find any long term (years) studies of the use of these drugs. (Maybe I just don't know where to look.) Sentinel (for example) did cause incoordination and tremors when treated at 5x the dosage. They tend to use beagles in these studies just because they are generally more healthy and hardy. Since certain breeds are more susceptible to some of these medications I really don't think it's a leap to suspect chemical intolerance in an animal. These drugs were approved for non-food animals. So I assume that they have not been tested for residule chemicals in the muscles like they would for a cow or pig. Basically is there a higher standard required for testing if it is a food based animal? Do Vets send in reports to the FDA if they have an issue with how a drug interacted with an animal?

I'm sure in areas where this is a big problem the benefits outweigh the disease. But unless they live somewhere like Florida there shouldn't be any mosquitoes flying around. I do understand that they won't guarantee that the dog would be free of worms, but I think they are beyond that issue. As far as flea control, unless their house is infested, they should be dormant. Seems like there has been a lot of chatter this year about the flea infestations. Are we overusing the flea medications to the point that the actual fleas are becoming resistant?

Meghane I realise you are a Vet. As with most forums I am just giving my opinion on what I would do if it was my dog. No, I would not spend that kind of money on an MRI. As with any test, I always what to know what are you looking for, and what would be involved in fixing the problem. Can this dog physically survive some kind of risky surgery? Can they financially afford it?

It's always a delicate balance trying to know when it's time to let your beloved pet go.

Housefairy, you are SO WRONG and should probably just stop now. Ivermectin is used in food animals ALL THE TIME. In fact, many people with many dogs buy the *cattle* ivermectin liquid from the feed store and dose it out for their dogs because it is cheaper than buying Heartgard etc. And trust me, there isn't a lot of drugs one is allowed to give to a food animal and they ALL have been more than thoroughly tested.

Yes, there is a 2-tiered adverse event reporting system in veterinary medicine. One report goes to the manufacturer and the other to the FDA for drugs, and to the USDA for parasite type medications (like flea control). Not to mention the fact that any suspicion of an adverse event is likely to be reported on any number of industry forums. So if among the millions of dogs that have been treated every month with all different types of heartworm prevention for many many years has not brought about any problems one can safely say that in very rare exceptions, they are safe drugs. And BTW, Sentinel (milbemycin) is the ONE drug that collie breeds SHOULD take instead of ivermectin because it is SAFER in these breeds. Even though the dose of ivermectin found in HWP has been proven to be safe for even MDR-deficient dogs.

There is a HUGE difference between a dog that is born with a congenital defect that renders it unable to have a proper blood-brain barrier and a normal dog. I don't know what you mean by "chemical intolerance." But if you are inferring that because a certain drug can cross an *abnormal* blood brain barrier that it must be a "bad" drug, you are wrong. It's a bad blood-brain barrier. That's like saying that peanuts are dangerous because some people are allergic. It's the abnormality on the specific animal, not anything at all to do with the drug.

Yes there are certain areas of the country where you don't need HWP and/or flea control all year. However there are many areas where you DO need it year round. I live in NC and I myself got bit by a mosquito on New Year Day in my house.

Opinions are fine and I totally agree with you about the MRI- I wouldn't do it either because I wouldn't change my course of action based on the results. But if you're going to say something that is NOT an opinion, it should be based in fact not conjecture.

Calm down I wasn't trying to offend you. Apparently I came across as harsh where I was just trying to explain, or understand, exactly what I was reading in the reports. Since I have a herding breed, yes I am interested in the studies. Also a prior pup I had must have had the mutant gene. That dog was allergic to every drug and always had to have benadryl. She was given some pain killers for an anal gland infection once and actually had a seizure.

The FDA publication report was stated for non-food based animals. Obviously that was because I was looking at a specific brand. That is also why I questioned if it made a difference between types of animals and if the tests standards are higher for food based animals. So yes, you are saying they are higher and basically they change the name and list those results in another report.

With human drugs, you just have to assume that there are a lot of safeguards in place to keep someone alert to potential problems. So it's reassuring that there are protocols in place in order to alert someone if there is a problem with a veterinary drug.

Since people can develop an intolerance for a drug, even if they have taken it for years, I would assume that rule can apply to all animals. As an example, my son who is a grown man, has taken ibuprofen for occasional pain relief. The last time he took it he ended up in the ER with anaphylactic shock. The ER Doctor said it was quite common. He can no longer use that brand of pain killer. Sure shocked the heck out of me. Now I would assume that also depends on the type of drug. That is why I was asking if this is a drug where intolerance has developed over time or due to age.

So I will duck out with my tail between my legs. Besides I'm getting the nose jab with the occasional scratch. It's time for an evening walk.

So sorry about your dog having seizures. My 11 yearold yellow lab started having them about a year ago.The vet couldn't find cause. He thought maybe a brain tumor. He wanted to start him on phenobarbital. We declined and tried making marijuana butter . The reason being we watched CNN show on CBD marijuana stopping seizures in humans. It seemed to work for about a year. Yesterday had a big seizure and now cant control urine .I am not recommending anyone use this treatment just letting you know our experience .Also, pumpkin is a great nutritional food for older dogs.