Warfarin is an anti-coagulant rodenticide that causes rodents to bleed excessively and die. In this week’s episode, Dr. Monica Sterk, emergency veterinarian and Regional Operations Director with Veterinary Emergency Group, describes the risks behind rat bait toxicity and what to expect if your dog does get into this poison. Hear what happened when one of her patients swallowed a dead rat and there was a concern the rat had been killed by rat bait.
Welcome, Dr. Sterk
[00:01:04] Dr. Lancellotti: Welcome, everyone, to today’s episode of Your Vet Wants You To Know. I have a very special guest with me today, Dr. Monica Sterk. She is an emergency doctor who is going to be talking to us today about warfarin, which is a type of rat poison. Dr. Sterk, thank you very much for being here.
[00:01:22]Dr. Sterk: Thank you so much for having me, Dr. Lancellotti. I’m so excited to talk about this and give people some information about warfarin toxicity.
[00:01:31] Dr. Lancellotti: Awesome. Can you tell our listeners a little bit about your background and what experience you have as an emergency room doctor?
[00:01:40] Dr. Sterk: Absolutely. I’m a regional operations director and also an emergency veterinarian at the Veterinary Emergency Group. I actually jumped right into emergency medicine right out of veterinary school and strangely enough, I fell in love with the nocturnal lifestyle of being an overnight ER doctor. I started working for VEG in 2018 and since then, I’ve grown into different roles as an emergency doctor, a medical director, and now a regional operations director for some of our New York and New Jersey hospital. It’s just been so much fun for me to be an ER doctor. I love this topic, specifically, because I know it can be very scary for a lot of owners to realize that their dog might’ve gotten into something like rat poison. It’s really satisfying to see them puke up that green rat bait and knowing that I can potentially save their life. So, it’s a really exciting topic.
[00:02:34] Dr. Lancellotti: Yeah, that’s great. I think getting this information out to pet owners will help them, not only if they’re going through a situation where their dog has eaten rait bait, but also to help them prepare, so that they don’t get in this situation in the future.
[00:02:47] Dr. Sterk: Absolutely.

He ate what???
[00:02:48] Dr. Lancellotti: As an emergency room doctor, you probably see rat bait and rat poison quite a bit. Is there any one case, in particular, that sticks out in your mind?
[00:02:58] Dr. Sterk: Oh, definitely. It’s kind of a funny story, actually. I had an owner who knew that her dog ate a dead mouse and she was worried the mouse might’ve died from rat poison. And of course, if her dog injusted that mouse, then we’re worried about the dog having rat poison within their body. So, she came in about 20 minutes after her dog ate that mouse and we gave the dog an injection of Apomorphine, and that made the dog really nauseous and it ended up throwing up. So what happened was, this dog threw up an entire huge rat completely whole. It didn’t even take one bite, it just ate the thing whole. Honestly, it was too funny, but it did the trick.
[00:03:43] Dr. Lancellotti: Wow. That’s great (disgusting, but great) that the owner was able to see that it happened, bring the dog in right away, and you guys were able to help, so that there was no issue whatsoever with the rat poison. That’s great.
[00:03:55] Dr. Sterk: Yeah, it was really phenomenal. The owner watched the whole thing and she couldn’t believe it.
[00:04:01] Dr. Lancellotti: Quite an ordeal. Huh?
[00:04:03] Dr. Sterk: It really was.
What does rat bait do to a dog?
[00:04:06] Dr. Lancellotti: Can you describe for pet owners, what is it that we’re worried about with rat bait? Why is warfarin such a scary thing? And what is it used for? What does it do in the body?
[00:04:20]Dr. Sterk: Warfarin is an anticoagulant (blood thinner), and that basically stops clotting in the blood. Many people (sometimes older people with heart conditions) can be on this type of medication to prevent blood clots from forming. It’s something that, in the body, we can ultimately stop by using vitamin K. It’s really the antidote and it’s super important for what we call the clotting cascade or the clotting process. Ultimately, it stops that vitamin K from doing what it’s supposed to do.
[00:04:56] Dr. Lancellotti: Yeah. Basically, that rat poison is designed to get rid of the rodent by causing it to bleed. That’s why it’s really scary if the pet gets into it.
[00:05:05] Dr. Sterk: That’s exactly right.
[00:05:07] Dr. Lancellotti: Obviously, if a pet owner knows their pet has eaten rat bait, they’ll want to get it into the vet right away. But what if they didn’t see the pet eat it? What might happen to first indicate to the pet owner that there may be a problem?
[00:05:21] Dr. Sterk: It’s ideal, of course, if the owner knows the pet has eaten this, but there are many times where it has happened to all of us. Our pets have their noses in the ground, and sometimes, it’s tough to know if they’ve eaten it or not. Usually, the signs happen a couple of days after the pet has eaten warfarin or a rat poison. What the owners usually notice is that their pets are vomiting (a lot of times with blood in it), they’re having bloody diarrhea, they’re super tired, and sometimes, they’re even coughing up blood. When you think of what warfarin does, it’s really an overdose of it, and too much of that will cause bleeding. If there’s not enough clotting, we’re now bleeding from our gums and our mouth. We’re coughing up that blood. Sometimes, we can see things like pale gums, or we can notice these types of bleeding out, so to speak.
What should I do if my dog has eaten rat bait?
[00:06:13] Dr. Lancellotti: So, if pet owners have seen that the animal has eaten the rat poison, or if they’re noticing any of these bleeding signs like bruising or bloody diarrhea, they shouldn’t wait to get to their veterinarian, so that they can figure out what’s going on. But once the pet is with the veterinarian, what tests might be recommended? What is the vet looking for?
[00:06:34]Dr. Sterk: If an owner knows that the pet got into rat poison right away, the first thing that I would do is induce vomiting. Just like that funny story I told you. We would use that injectable medication, make the pet feel nauseous, and then they would vomit up the rat poison. The hope is to get as much of it out as possible, so that there’s minimal time for it to get absorbed in the body. Then, I’ll use activated charcoal to help stop any binding. Just like how people at the hospital get their stomach pumped, it’s the same type of thing. So, if the owner doesn’t know about the ingestion, of course, it’s a little trickier to figure out, but those signs that we just talked about can make it a little more clear. The first thing I would do is my physical exam, to look for any abnormalities such as bruising, pale gums, muffled heart sounds, etc. Those things can clue me into some bleeding in places where there’s not supposed to be. Usually, after my exam, I’ll probably do a quick scan with the ultrasound to look for fluid in places where it’s not supposed to be. Of course, that fluid would likely be the blood that we’re looking for. The other important thing to check for is anemia (a low number of red blood cells). Again, if we’re bleeding, we’re going to have that low number of red blood cells and we’re going to check for the pet’s clotting time. When the clotting time is really long, it really clues us into that warfarin toxicity.
What is the treatment for rat poison?
[00:07:56] Dr. Lancellotti: Those are all really important tests to do to help you figure out exactly what’s happening and how you can help the animal. Once the veterinarian knows that this is very likely warfarin toxicity, what options are available to help those pets?
[00:08:13]Dr. Sterk: It really depends a lot on how severe the poisoning is. If we got a lot of that rat poison out by making the pet vomit, sometimes we could treat with that activated charcoal and monitor the pet as an outpatient (it can go home). This would mean that we would check those clotting factors pretty regularly in the following couple of days, and the pet would be on vitamin K supplements for the next 3-4 weeks. If the pet is super sick from the warfarin poisoning and already showing signs of that bleeding, a lot of times, we’ll need to do things like a blood transfusion, keep the pet hospitalized, and really push high doses of that vitamin K. A lot of times, they’ll need things like IV fluids, we need to check their blood pressures, and do that blood transfusion to really replace the blood that they’re losing.
[00:08:59] Dr. Lancellotti: So hopefully, the pet owner is able to get the animal into the hospital in time, but if not, they’ll be able to get things like blood transfusions and supportive care, so that they can get through this poisoning and come out the other side.
[00:09:12] Dr. Sterk: Absolutely. That’s exactly right.
How can you prevent rat bait toxicity in your dog?
[00:09:14]Dr. Lancellotti: Obviously, it’s a really scary situation for any pet owner to be in. What advice do you have for preventing it from occurring?
[00:09:22]Dr. Sterk: If you have something like a gardener or landscaper, make sure to talk to them about what they’re using around or in your home (as far as rat poison), if they’re going to be using it at all. A lot of people live in apartment buildings and may not even know that the landscapers put these traps or baits around the buildings. So if that’s the case, remember to always walk your dog on a leash, make sure you pull them away from putting their noses behind bushes or areas you can’t really see. My last piece of advice- if you have a rodent problem and you use an exterminator, make sure you talk to them about your pets and your family, and make sure to mention that your pet may be pretty curious and be one of those dogs that really gets into things.
[00:10:06] Dr. Lancellotti: Yeah, that’s all really good advice. We talk so much about prevention on the show, and making sure your pet doesn’t have access to these poisons will certainly go a very long way to preventing these serious problems. For our pet owners who may have been in a situation where they think their pet has eaten rat poison, do you have any big takeaway points for them?
[00:10:26] Dr. Sterk: Yeah, absolutely. If your pet got into rat poison, I don’t want you to panic. I want you to head to your nearest emergency hospital. You may want to check out Veterinary Emergency Group, but definitely try to bring that packaging or the information of the type of rat bait that was ingested. That’s going to be really important. And remember that if this is warfarin toxicity, there is a cure. As long as we catch it early, and the sooner we can start treatment, the better.
[00:10:52] Dr. Lancellotti: That’s perfect. Thank you so much for sharing this advice to pet owners. It’s always a good idea to know where your nearest emergency hospital is so that in the event that there is an emergency, you know exactly where to head without panicking and trying to figure that out in the moment. You can find the nearest veterinary emergency group near you at https://www.veterinaryemergencygroup.com. Many family veterinarians are comfortable managing pets with warfarin toxicity, but again, you should find out where the closest emergency hospital is to you, so that you’re not panicking to try and find an ER when you need one. There’s also a link for the American College of Veterinary Emergency and Critical Care Specialists on the website, if you want to find a specialty hospital near you. I would encourage you, if you’ve been through warfarin toxicity with your pet, join the Facebook group and tell us about your experience. Let us know what other topics you want to cover. We love feedback and hearing what you want to hear on this show.
Scratching the Itch
[00:11:53] Dr. Lancellotti: At the end of each show is the ‘Scratching The Itch’ segment. This is a short segment that highlights something, either a human interest story, a product or a website that either provides relief or just makes you feel good. So, Dr. Sterk, I was wondering if you had a ‘scratching the itch’ you would like to share with us today.
[00:12:12] Dr. Sterk: Yeah, absolutely. It’s something that I do every year and I encourage a lot of people to do it. It’s called a happiness jar. Basically, throughout the year, you use a jar (whether you decorate it or just a plain and simple box or jar), and you put in different memories or different notes about things that happened to you throughout the year. You got an A+ on a paper, or you traveled somewhere and have the ticket from the plane, etc. All these things that have made you happy over the year, you put in that happiness jar. At the end of the year (or right after New Years), you open up the jar, you look through everything, see how amazing your year was and all these things that have made you so happy. I love doing that. It’s something that I really encourage. It takes no more than five minutes, and I think it’s something really great to inspire you and remind you what a great year you had.
[00:13:07] Dr. Lancellotti: That’s a really fun concept. I like that a lot. Especially, at the end of the holidays, right at the beginning of the new year. You’re taking all the decorations down and things are going back to not being as bright and cheery in the middle of the bleak winter. That’s a perfect time to open up that happiness jar and look at all these wonderful memories you had from the past year.
[00:13:26]Dr. Sterk: It’s so true. A lot of times, it can be a little bit quiet during that time of year. So, it’s a nice reminder.
[00:13:32] Dr. Lancellotti: Yeah, that’s excellent. If any of our listeners have suggestions for Scratching The Itch, I would love to hear that, so that we can feature that on an episode in the future. Dr. Sterk, thank you again for coming on and talking to pet owners and helping to educate them about this (potentially) very serious condition. I really appreciate your time.
[00:13:51] Dr. Sterk: Thank you so much, Dr. Lancellotti. It was a wonderful experience and I hope that everyone got some great information out of this.
[00:13:59] Dr. Lancellotti: And for everyone out there listening, I look forward to your next visit with Your Vet Wants You To Know.
Resources:
https://www.merckvetmanual.com/toxicology/rodenticide-poisoning/anticoagulant-rodenticides-warfarin-and-congeners
Emergency Procedures for the Small Animal Veterinarian 3rd Edition – Plunkett