Cluster Seizures in Dogs


Controlling cluster seizures in Springer

Question: Dr. Mike, I came across your web site some time ago when I was researching some problems my dog was having. I think you provide a wonderful service to pet owners and now I've become a subscriber. I have a 14 year old female springer spaniel who is again having problems. I noticed that she was moving her head in an up and down motion with a fixed stare, her teeth clinched together while the rest of her body remained still. I thought that it might be some kind of seizure. I recorded a video of what was occurring and took Brandy to my vet. My vet ran blood work and the results were glucose 92, Bun 28 (H) expected 20 - 20, creatinine 0.7, sodium 148, potassium 5.3 (H) expected 3.5 - 5.1, chloride 102, NA/K 27, calcium 10.2, phosphorus 5.3 (H) expected 2.9 - 5.0 with a note that test result falsely elevated by condition of the sample, total protein 6.3, albumin 2.4 (L) expected 2.6 - 4.0, globulin 3.9, total bilirubin 0.2, alk phosphatase 366 (H) expected 20 - 130, ast 14, alt 29, ggt 6, ck 31, amylase 1,078, lipase 267, cholesterol 241, osmolality 299, IGM negative, IGG negative, hemogram - WBC 9.1, RBC 5.84, HGB 15.4, HCT 45.2, MCV 77.4 (H), MCH 26.4 (H), MCHC 34.1, platelet count unable to report due to excessive clumping but estimate appears to e at least 200,000/CU. MM. or Greater. RBC morphology normal, Differential - segs 78, bands 0, lymphs 16, monos 3, eosinophils 3, basophils 0, ABS Segs 7.0, ABS Bands 0.0, ABS Lymphocytes 1.4, ABS Monocytes 0.2, ABS Eosinophils 0.2, ABS Basophils 0.0. Erchichia and valley fever were also negative. My vet said that her blood work indicated she was quite healthy for her age except for being low on protein. My vet wanted me to take her to a specialist whom she consulted with and the specialist wanted to do a cat scan on her, but due to the excessive cost of $900 to $1500 for the cat scan I am unable to take her. My vet put Brandy on phenobarbital, 30 mg twice a day. Brandy is also on etogesic 1/4 of a 300 mg tablet once a day for arthritis and she also has hip dysplasia. She is on hydroxyzine 25 mg 1 pill a day for allergies and CNM hypoallergenic dog food. Since all of this started I've not been giving her the hydroxyzine which hasn't really affected her much at this time of year. The phenobarbital has left her complete drugged and the seizures have not stopped. She can't get up from the floor by herself and when she is up she usually falls back down. Two weeks later my vet increased the phenobarbital to 1 1/2 pills twice a day since the seizures were not stopping. This only made the problem worse. Since I was having problems getting the dog up and about, my vet decided to do blood work early checking the level of the phenobarbital in her system. This came back at 24 which was between the level of 15 and 45. I was told that the phenobarbital level could be increased based on this test. I didn't want to do that since the dog isn't mobile at all. I then asked my vet to do a thyroid test on her which I was told wasn't necessary but it was done anyway. The test came back with a low thyroid reading at a -.5. Brandy is now on thyrotabs .3 mg twice a day. She has been on this medication for 11 days. The seizures have slowed down, but have not stopped. Brandy was having from 8 to 10 a day, but now is at 5 or below. I know that the phenobarbital could have given a false reading on the thyroid test, but she has improved since taking it. I had to take Brandy in for more blood work a week ago because I was having trouble getting her to eat. This blood work was to check on her kidneys and liver. The kidneys were good, but the level of the alk phosphatase was 384 with normal listed at 186. Now I'm being told that her liver could be failing due to the phenobarbital. Is this test accurate? Would the phenobarbital cause an elevated level in liver enzymes? The phenobarbital the dog is taking has been reduced back to 30 mg twice a day based on this blood work. I was also told that potassium bromide is processed through the liver so that won't work. I thought that potassium bromide was processed through the kidneys. Which is correct? Is there any seizure medication that is not processed through the liver? From looking at other areas in your web site you mentioned a bile test. Can you tell me what is involved in that test? I have to take the dog in on Monday for more blood work. I've been told not to feed her that morning. My vet wants to check the phenobarbital, thyroid, liver, etc. again. I know that I'm grabbing at straws, but I truly want to help Brandy and the seizures have been slowing down. Yesterday she didn't have any. I apologize for the long e-mail, but I wanted to make sure I gave you all of the information. I would really appreciate any help you can give me. Thanks, Vicky

Answer: Vicky-

There are three things that I have to remember to put in this note, so I am going to put them in now, before I forget. The first is that the rise in alkaline phosphatase after administration of phenobarbital is normal and should not be viewed as a symptom of liver failure unless there are other supporting signs, such as a rise in ALT levels, increases in bilirubin or abnormal bile acid response test results. The second thing is that phenobarbital does not exert much antiseizure activity for the first two to three weeks of use but it does cause a lot of side effects during that time, such as the weakness and incoordination that you have been seeing. Potassium or sodium bromide takes about a month (with a loading dose) or about 2 to 3 months (without a loading dose) to have stable enough serum levels to exert a continuous anti-seizure effect and it also causes many of the same signs as phenobarbital with initial use. The last thing is that bromide does not commonly cause liver damage or kidney damage.It is usually thought to be non-toxic to these organs. It is excreted in the urine and it is pretty much unchanged when it is excreted.

Control of cluster seizures on an immediate basis can sometimes be obtained using diazepam (Valium Rx). We dispense the injectable form of this medication to the client but advise that it be given rectally, mixed with a lubricating jelly. It seems to sting a little when it is administered but most pets tolerate it well enough that it can be used at home. This makes it possible for the seizures to be controlled while waiting for the phenobarbital or bromide to begin to work.

There is some possibility of kidney damage with the increased BUN and high phosphorous levels. It may be best to use sodium bromide instead of potassium bromide in patients with kidney disease but this is probably not absolutely necessary with the levels in the lab work.

Bile acid testing is usually done by fasting the patient for at least twelve hours, then drawing a baseline blood sample. A small meal (at least a couple of tablespons of food) is fed and then a second blood sample drawn two hours later. In patients with liver disease the baseline bile acid level may be high and/or there may be a significant rise (above the normal rise) in the bile acid level in the second blood sample, indicating that the liver is having problems functioning properly.

Hopefully you have seen improvement with the combination of phenobarbital and bromide. If this works well but there are still intermittent clusters of seizures, adding diazepam at the time that seizures occur can be helpful. If your vet needs information on this therapy, it is described in the new Kirk's Current Veterinary Therapy (XIII).

Mike Richards, DVM 3/23/2001


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...