I’m writing this post several days after everything has returned to normal, in part because I was a bit emotional about the situation while it was in progress.
A couple of weeks ago, big Sheltie boy Copper (who is as big as a largish Collie and deaf) was having bloody diarrhea. It seemed consistent with giardiasis, which had been brought into the house (and yard) by Tigger, the puppy who’d been with us for only a few weeks. Diarrhea is, of course, hard on one’s system and we didn’t want to risk Copper getting dehydrated; it’s also hard on the carpets when a dog doesn’t get outside in time, and it’s easy for the yard to get continuously re-contaminated and causing infections in other dogs.
Consequently, we jumped right onto the situation to get it under control as quickly as possible. We started Copper on a regime of metronidazole (generic for Flagyl®), which is a recommended antibiotic (which we stock because of its broad usage) for a number of intestinal infections, including giardia. He seemed to improve over the next day or two, but both Barbara and I sort of vaguely noticed (without mentioning it to one another!) that Copper seemed slightly “out of it”, maybe a little awkward or clumsy. We didn’t think too much about it (which is probably why we didn’t say anything to one another about it) until about the third day when he was clearly and significantly ataxic!
Ataxia is, of course, the word used to describe loss of coordination of muscle movements. In this case, it manifested itself as a very wobbly and uncertain walk and difficulty in standing. Poor Copper finally laid down (“collapsed” is only a slight overstatement) and couldn’t get back up. Now, most of you haven’t met Copper, so you don’t know that he’s got this fully little head tilt that we think might be related to his deafness — the vet thinks that both may have been caused by an encounter with a car when he (Copper, not the vet) was about a year old. Well, his head tilt was noticeably worse, and his limb movements became very jerky and he got a bit rigid. In short, he was not doing well at all!
These symptoms are known side effects of a metronidazole overdose! Fortunately (well, unfortunately, in a different way), we’d seen this before. Some years ago, we’d actually given an overdose of metronidazole to Annie, an ancient and abused Sheltie we’d rescued from down in St. George. She had similar symptoms, so it was familiar, but also quite scary. Naturally, we immediately stopped giving Copper the medication. A little research revealed that he’d been getting a 33% overdose for a couple of days. That’s not horrible, but apparently he is somewhat sensitive to that medication.
Now, most of us would think that a dog would start to improve…or, minimally, not get any worse…when you stop giving him the thing that’s causing the problems. Not so… By that evening, he was significantly worse. I was seriously wondering if we were going to lose him. Naturally, it was Friday evening after Cottonwood Animal Hospital had gone to emergency room hours (and costs). Barbara phoned them, but the ER vet on duty was somebody with whom we’d never worked and she wouldn’t give us the time of day over the phone. (Side note: I guess that’s not unreasonable, since the vet didn’t know us, but we’re used to dealing with vets at Cottonwood who know us and our experience level and are thus willing to give advice based on our descriptions, etc.)
To avoid the much-higher costs of taking a dog to the ER, and because we’d had experience with this problem before (and because Barbara was doing extensive research about this problem on the web), we decided to keep Copper at home. We knew that the medicine would gradually, over three to six or seven days, leave his bloodstream, and Barbara’s web research uncovered the fact that phenobarbitol (yes, the anti-seizure medication) was reported to help detox from metronidazole overdose! Who would have guessed? And, yes, we stock phenobarb because of the various seizure dogs we’ve had over the years.
So we started giving Copper subclinical doses of phenobarb, which really did seem to help. It’s less that it seemed to remove the metronidazole from his bloodstream than it controlled the neurological effects of the metronidazole and reduced his ataxia and other symptoms.
Recall that I mentioned above that Copper is Collie-sized? That includes his weight, roughly 30 kilograms (65 pounds). No way could Barbara pick him up, and it was incredibly difficult for me to lift his dead weight while he was lying down. And he couldn’t stand! Obviously, I couldn’t hold him in an appropriate position outside for him to pee or poop, so for a couple of days, we had no choice but to allow him to just pee where he was lying on the floor Poor guy…he was extremely unhappy about that, but we put him on a pad that would protect the floor and carpet.
After a couple of days, he was able to sort of pull himself into a sitting position, so I did pick him up and carry him outside. When I set him down on the ground, he was actually able to (barely) stand for a few seconds while he peed, and I snatched him back up before he collapsed into the puddle he’d just made. Back inside onto his pad he went. The next day, same thing, twice…and on the first time, he was able to take a couple of steps without collapsing. Next day, more of the same, but he could walk a little bit more. Still, he wasn’t willing to tackle walking down the ramp or back up it to get back into the house, so I continued to carry him in and out. By the day (Wednesday) I had to leave for a 2-day business meeting in California, he was clearly on his way to recovery, but I was still carrying him in and out, although he could manage to pee and poop by himself while outside.
When I got to my hotel Wednesday night and phoned Barbara, she had the superb news that Copper had actually been able to walk outside, do his business, and walk back in. He was, she said, still a bit wobbly, but clearly much better. By the time I got home late Friday night, Copper was almost 100% back to normal…just a little extra head tilt and a slight tendency to get tired and have to lie down more often than normal. And, by today (Monday, July 5), he appears to be completely normal, like it never happened.
Poor guy! We tried to help him overcome one problem (diarrhea) and created another, rather scary, problem. He was clearly scared about what was going on, but he trusted us to do the right thing for him and he let us do what had to be done. He was such a good boy about the whole thing, and obviously grateful that we were willing to carry him in and out.
Lesson learned! Check the dosing very carefully before giving medications! And know your dogs’ weights!!
Oh, and to make matters really frustrating…we finally concluded that poor Copper’s diarrhea wasn’t caused by giardia after all, but that he’d picked up coccidia (which also came into our house courtesy of Tigger). And coccidia should be treated with sulfadimethoxine (generic for Albon®), not metronidazole.