Please be very careful about giving your dog the antibiotic Keflex (cephalexin). The vet prescribed it for our dog to treat an infected hotspot. One week later he’s lame in the hindquarters, weak and in pain.
This is, apparently, a common reaction to Keflex and a known side-effect of the medication in dogs.
Keflex, though widely-prescribed for dogs, is an Off label medication. It hasn’t been FDA approved for use in dogs, and therefore has never been fully-tested for use in dogs. The vet who prescribed this drug for our Bernese Mt. Dog had never heard of the lameness as a side-effect, in part because the side effect is rare, but also because the medication is canine-tested only in the field. The information on Psuedo HOD Polyneuropathy (the official name for this condition) is coming from breeders and other pure-bred owners who have seen this reaction in their pure breeds.
I just wanted everyone else out there to be aware.
Update: For those who find this page while searching for terms like such as weak hindquarters, lame hindlegs, paralysis and all the other terms I used when doing research I decided to add a progress diary.
Day 1: Wednesday
Dog was anorectic and non responsive, with a lot of roaching (pronounced curvature of the spine). Discontinued antibiotic, continued previously prescribed Prednisone 20mg 1/day.
Day 2: Thursday
Dog weaker, still anorectic. Responsive to normal trigger words and phrases (“go for ride”; “guys”; “would you like a treat?”). Roaching still pronounced, with abdomen slighly distended. A visit to the veternarian ruled out bloat. The vet examined the dog manually and diagnosed possible Spondolyitis–arthritis and bony growth of the lower spine. I told the vet the roaching had been seen previously in the dog when he was dealing with gastric issues and that I suspected Keflex side-effects of gastric upset. The vet advised 24 hours NPO followed with a continued course of cortisone. While at the vet’s office the dog eagerly ate hand-fed treats, leading me to suspect either the positioning or type of food he had at home was unappetising.
Day 3: Friday
Dog making whimpering noises while he breathes, drooling excessively. Having a hard time without food and water. At 22 hours NPO decided to give the dog coritsone, food and drink. Dog eagerly took 1 dose of cortisone camoflaged in cream cheese, followed by limited water. Three hours after dosing the dog eagerly ate scrambled eggs. Still very lame in hindquarters and demanding constant attention.
Day 4: Saturday
Internet research confirms that pseudo HOD is a known reaction to Keflex, seen mostly in large breeds with more esoteric breedlines. (In short, this happens mostly to pedigreed dogs with tightly controlled breedlines like Bernese Mt. Dogs and Great Danes. It doesn’t happen all that often at all in mixed-breeds.) Internet advice confirms the best treatment is corticosterioids and bed rest. I can find no set length of recovery times, ranging from 3 days to 16 weeks. Titrated up the cortisone to 2x daily. Higher dose seems to have better effect. The dog’s aspect is clear and bright, but hind legs are still lame.
The dog doesn’t seem to be in any pain; the issue seems to be more neuropathic–as if his back end were “asleep”. Since he is not in pain, but more discouraged from the lack of limb function, I’ve decided to give him periodic exercise to prevent atrophy and bedsores. I walk him short distances every 3 hours.
Day 5: Sunday
The dog is much improved, moves around better and has fully regained his appetite. He still has some lameness in the hindquarters–I think we’re looking at a longer recovery time than the earliest estimate of “three to five days”.
Day 6: Monday
I had reduced the cortisone dosage on the advice of the vet to one pill every 24 hours. This seems to cause the dog some discomfort. Stepping the cortisone back up to 2 pills every 24 hours and handfeeding the dog to make sure of maximum nutrition. We are still taking brief walks in order to preserve long term limb function. He is drinking a lot of water–a side effect of the cortisone–and therefore he’s peeing a lot. Sadly, he has been having to pee in a modified squat. Monday, Day 6, was the first day he was able to pee while lifting his leg, in the traditional “boy dog” stance.
Day 7: Tuesday
Breakfast of scrambled eggs and oatmeal, followed by lots of water. The dog slept peacefully for 4 hours following his morning dose of cortisone–an improvement. His sleep over the last few days has been marred by much whining and yipping of discomfort. At noon he went outside for his usual evacuation, and was able to pee twice with his leg lifted, and defecated. (Moving his bowels presents more of a challenge given the problems with hind-end posture.) He is eating some kibble again and drinking liberally. His noon walking time had fewer stumbles and more upright time.