[From Tufts December 2010 Issue]
This is the first of an occasional column by best-selling author Nicholas Dodman, BVMS, DACVB, director of the Animal Behavior Clinic at Cummings School.
When Bernie was first brought to see me, he was 2 years, 10 months old. His owner, a charming older woman living alone, clearly doted on Bernie. A castrated male, Bernie was first acquired by the woman from a breeder when he was 8 weeks of age. He spent his days lounging around in her home, living the good life with his 7-year-old spayed female Akita housemate.
But then it started. At 2 years of age, he started exhibiting bouts of really bizarre behavior. These bouts took the form of star gazing, fly snapping (at imaginary flies), air licking and lip smacking. During these bouts he appeared somewhat fearful, bolting from room to room as if trying to flee some unseen enemy. Obviously, his owner was extremely worried by what she saw.
Although “attention seeking” can cause all kinds of odd behaviors to occur in dogs, that was clearly not the case here, as Bernie would exhibit the behavior even when removed from his owner.
Our first job was to rule out any medical causes for the aberrant behavior, as any sudden onset of strange behavior like Bernie was showing can and often does have medical roots. Physical examination and comprehensive blood work did not indicate any organic problem with Bernie, leaving us with only two possibilities. The first was that he was showing some atypical from of compulsive disorder, and the second was that his behavior was a result of complex partial seizures.
The tie-breaker test to distinguish between these two possible causes is an electroencephalogram (EEG), so that’s what we did. Bernie had to be put under light sedation for the procedure, which took only about 30 minutes. Acupuncture-needle-thin electrodes were carefully positioned across his scalp and the recording was begun. The traces on the EEG machine danced as they recorded electrical activity going on in Bernie’s somnolescent brain. The EEG confirmed the seizure diagnosis and even pinpointed the region inside his brain in which aberrant electrical activity was occurring.
“Berners” are no strangers to epilepsy so this made good sense. Our treatment entailed the use of huperzine-A, an extract of Chinese club moss (Huperzia serrata) that has been shown to reduce seizures in other species. I first heard about it from expert human neurologist Steven Schachter of Harvard’s Beth Israel Hospital in Boston. The herbal extract, he told me, has known pharmacological properties that can be useful in Alzheimer’s disease and seizure management.
After initiation of treatment with huperzine-A, Bernie’s odd behaviors were almost entirely suppressed for six months. Then the local veterinarian began treating him with an opioid analgesic medication, Tramadol, to ease some orthopedic pain he was experiencing as a result of an ongoing hip problem. This medication is known to lower the seizure threshold and, sure enough, right after it was initiated, Bernie’s abnormal behaviors returned at full strength.
Adding a more conventional anti-seizure drug, phenobarbital, suppressed Bernie’s attacks once again and all was well again in his household though further adjustment of doses were necessary over time.
Bernie has been pretty much controlled for a couple of years now. The lesson to be learned from his case is that partial seizures can and do occur in dogs, but they are not always easy to diagnose. In humans, partial seizures are more common than “grand mal” (tonic-clonic) seizures. But note: People with partial seizures can tell their doctor what they are experiencing. In dogs, all we can do is observe them very closely to determine that their sensations and emotions are somehow affected.
Some veterinarians, veterinary neurologists included, do not even accept that partial seizures occur in dogs but that seems a somewhat dogmatic view (no pun intended). Most often, conditions that affect humans — ranging from heart failure to obsessive-compulsive disorder — also affect dogs, though sometimes in somewhat different ways. The fact that “putative” partial seizures respond at all to anticonvulsant medications is powerful evidence in favor of their occurrence.
Though not all of these types of seizures respond as well as Bernie’s did, a useful level of improvement often can be obtained in most cases with the right kind of treatment.