Snake Bites

By Dr. Jeffrey & Deb Haines

With those of us in the Northern Hemisphere coming into snake season, I felt that it was appropriate to make a post about venomous snakes and our pets.

Of the roughly 3500 species of snakes in the world about 6% are venomous enough to present a possible medical concern. All snakes play an important role in the ecosystems that they are a part of. They are particularly important in regards to rodent and infectious disease control. While we acknowledge their importance, we all fear for our family both furred and hominid when it comes to venomous snakes, all of us except the Irish and New Zealanders of course.

The best tool on our belts is education. Look up the species of snakes in your geographic region as there are plenty of good resources to help you visually recognise a potentially dangerous species and carefully leave the area if you come across them in their home. If you see one around your home calling a relocation professional and keeping everyone inside until they arrive is the safest call. Most snakes will move on as they are just wandering through or will leave with a good squirt with the hose. Eliminate property clutter and keep rodents down to keep snakes from enjoying the stay. Trying to kill the snake may be illegal depending on how endangered the species is and most snake bites to people occur when someone untrained is trying to move or kill a snake.

If you suspect that your pet has been bitten by a venomous snake, immediate examination and consult is recommended to assist in determining necessary treatment which will depend on the species of snake, how much venom was administered, time from bite, and location of bite among other factors. There is often no first aid recommended beyond keeping your kiddo as calm and still as possible with the bite below the heart if possible while transporting to your nearest vet. If you see the snake, try to safely take a picture from a distance if possible(do not get near the snake.) An ID will assist in identifying the species and appropriate antivenom if needed.

This post was specifically snake bites in cats and dogs

One common question I get is for rules for visually identifying which snakes are venomous and which are part of the vast majority of harmless species(if a cat is harmless then most snakes qualify.) There are no hard and fast rules but there is a lot of misinformation out there about things like pupil shape, head shape, and colour patterns which may only help in certain places.

Some of the commonly encountered venomous snakes of North America. (Size not to scale)

QUESTIONS AND ANSWERS

1) Is it true there are no venomous snakes in Maine? That’s where I’m from and that has always been the hard and fast knowledge. Dr. Jeffrey …..it’s true, there are no species of venomous snakes in Maine.I suppose a timber rattlesnake could wander that far North but Maine isn’t part of their current range with population decline.

2) Would you recommend the rattlesnake vaccine 💉 . I have 2 pit bulls and yesterday we entered our first rattlesnake here is Tucson, AZ at the dog park and my one dog was very curious about it. Dr. Jeffrey … rattlesnakes are the main concern where I am currently as well. With the rattlesnake vaccine it’s important to decide if the benefit outweighs the risk. I sometimes administer the vaccine to my patients that are higher risk due to property location, outdoor activity, and to be honest the intelligence of my patient 😜 I have some loveable but not bright enough for self preservation patients that are higher risk for a bite.

3) What is the risk involved in rattlesnake vaccination? Dr. Jeffrey …. I have not seen any adverse reactions in my patients but the main one would be allergic reaction like any medication/preventative/herbal.

4) There’s a vaccination for rattlesnakes ? Dr. Jeffrey … there is but there is a lot of controversy surrounding it’s effectiveness. Snake bite frequency depends on your exact geographic location but isn’t the most common emergency seen in most ER’s by leaps and bounds. Rattlesnake Resolutions – Reptiles of Arizona
Natural Solutions Wildlife Enterprises – Rattlesnake Aversion Training

5) Do the little ones without rattles bite? Dr. Jeffrey … The very young snakes can definitely bite and their venom is the same potency as the adults. While an adult snake may be more likely to deliver a dry bite to conserve venom(it’s a valuable resource that takes a lot of resources to produce) the volume of venom from a large snake bite still often exceeds that of a young snake. Either way medical attention is still advised.

6) How many of the venomous snakes in Australia have anti-venom available? Dr. Jeffrey … there are Black snake, Taipan, Death adder, Tiger snake, and Brown snake antivenoms. It’s always important to know which hospitals around you stock antivenom products so you aren’t wasting time in an emergency.

7) I’m now a bit afraid to allow my guinea pigs to roam in the yard (supervised and enclosed), so I suppose I should look into what’s in Michigan. Dr. Jeffrey … the Eastern Massasauga Rattlesnake is the only venomous snake found in Michigan. It is considered a threatened species and you are unlikely to come across one.snakes are highly scent oriented and many follow rodent trails to find food. If you are in an urban or suburban environment you would be unlucky to find one I suspect.

8) We carry antivenin, but rarely use it. We have water moccasins and cottonmouths in Missouri. Dr. Jeffrey ….one of those things that you need to have on hand but hope you don’t have to use right? Unfortunately that drives up the already expensive cost as it often expires before use. It always hurts presenting a bill for antivenom.

9) Are there water moccasins in Michigan? If yes, are they poisonous? I grew up hearing we had water moccasins and rattlesnakes in Michigan. I read your post above about only one snake being poisonous in Michigan…the rattlesnake that is endangered. Dr. Jeffrey ….. water moccasins do not occur anywhere near Michigan but Northern water snakes are unfortunately often mistaken for venomous snakes and are often terrorised for it. I’m not the type to browbeat people over this point but some people will get a bit dramatic about the poisonous vs venomous distinction. Poison needs to be eaten while venom is injected, interestingly there are a couple of snakes in the world that are considered poisonous as well if ingested due to the toxins that they accumulate from their poisonous prey 😁https://www.wideopenspaces.com/a-quick-guide-to-all-18…/

10) Is there a best source to look up and learn about snakes in our region? For example, I’m in Richmond VA but originate from Pennsylvania so don’t know much about wildlife here and would love to learn more from the most reputable source. Dr. Jeffrey …. http://www.virginiaherpetologicalsociety.com/…/snakes…

11) Do you recommend rattlesnake avoidance training? Most seem to use shock collars. I am looking around for other options but not having much luck. Dr. Jeffrey … I recommend it based on risk assessment evaluated with a thorough verbal history/lifestyle discussion. For the patients that benefit from it a couple of low voltage shocks(I usually don’t advocate positive punishment training) can save lives.

12) Red against yellow, kill a fellow, red against black play for Jack.. is how I remember it! Rattles are pretty easy to spot, I live in Texas. Also… I hate snakes so venomous or not I let them be! Dr. Jeffrey …that rhyme is only of use in specific North American geographic locations but it does help if you live there.

13) I live in Arkansas and have an issue with water moccasins, copperheads and mainly rattlesnakes. I took one of my dogs after being bitten a few years ago to the vet and he said that our fur baby would be just fine unless he got hit by a car……he passed 2 hours later. This devastated me and I do not ever want one of my babies to go through that. The nearest vet that might have antivenom is a couple of hours away. Is there anything I can do for my babies? It terrifies me to let my dogs even go outside to potty. There is no aversion training near me. We keep the grass mowed short, I put a fence up and surrounded it with mothballs that get put out every month or after any rain storm. Please any advice for if they get bit and any other advice that will deter them from getting close to the house? Dr. Jeffrey …the rattlesnake vaccine is a relatively controversial option to help make reactions possibly less severe. It’s a shame you don’t have aversion training near you but you sound like you’re making your property less appealing to snakes and decreasing risk. Make sure there isn’t additional brush in addition to keeping the grass short and make sure you have good rodent control. If you see any non-venomous snakes around leave them be as they will help keep the venomous ones away. Dr. Jeffrey … the main controversy is regarding its efficacy. I would treat a vaccinated dog the same as an unvaccinated dog. Diphenhydramine(Benadryl) is part of some vet’s treatment plan for certain bites and exact scenarios. If I lived very far from an emergency hospital I might consider giving my own dog an appropriate dose like with a bee sting but I certainly wouldn’t rely on it unfortunately. Dr. Jason Sweitzer …I’d add that the vaccine has more local reactions at the site administered. So it’s hard to give something when we can’t really prove it works, and at best you still need the same treatment but Maybe they will do better. Dr.Re Fischer ….. I have had clients use benadryl when they could not get to a vet and for the most part, it worked on the rattlesnake injuries, depending where the bite was. They still swelled up, but the clients continued with the benadry for a few days.

14) In Australia I’ve always had snake educators say you can’t identify from looking.

In the last demonstration I saw he had 3 snakes which the crowd identified as red belly black (relatively harmless), tiger (bit of trouble) and king brown (lots of trouble). All 3 were actually brown snakes. It’s extremely difficult to tell by looking at the colours and patterns to identify the species. Also, more as a question but would immobilisation and a pressure bandage help like it does in humans? Dr. Jeffrey …..pressure bandaging is something I would recommend in Australia(where I went to vet school and got a lot of fantastic venomous snake experience.) In species that cause a lot of local tissue swelling bandaging can be painful and dangerous if applied too tightly. Ability to pressure wrap depends on the location of the bite obviously and should be temporary for transport.

15) You mentioned cats and dogs getting bitten–how often do cats actually get bitten by venomous snakes? Dr. Jeffrey ….. overall? Not very frequently and a majority recover with appropriate treatment just like people these days. Some parts of the world are obviously riskier though.

16) I live in MO we live in a forest and have copper heads. My daughter had a cat that died from a bite. I have a young Weimaraner and I’m very concerned. What is the treatment/ survival for such a bite in my dog? Dr. Jeffrey ….of the venomous snakes found in the state of MO copperhead bites carry the best prognosis with a possible 100% success rate of treatment based on the studies. Rattlesnake and cottonmouth bites are more dangerous. The key is rapid treatment which is often unfortunately costly due to high overhead clinic costs of treatment.

NOTE …. Dr. Jeffrey ….I hope no one needs to hear this but tourniquets and attempts to suck out venom or open up snake bites with a razor are not recommended in people or animals and are outdated. Antique snake bite kits are amusing collector pieces and nothing more.

17) Why except irish and new zealanders ? Dr. Jeffrey … well, only while living in their home nations. There are no venomous snakes in several island nations including Iceland, Greenland, Newfoundland, Ireland, New Zealand and the Falkland Islands. There are also none in Alaska or Hawaii.

18) Growing up in Florida/visiting my parents second home in Alabama there have been many venemous snake encounters. From water moccasins to rattle snakes to pigmy rattlers to coral snakes. My dad always kept a sawyer extractor in his truck in Alabama. He’d known quite a few lives to be saved by those in route to a hospital from rural areas. Best practice with snakes is to leave them alone. We learned growing up to avoid any holes we saw in the ground. Dr. Jeffery …I’m glad that the people your dad helped survived their bites. These days people seldom die from snake bites thankfully with fatality on a national average of about 0.06% with modern medical advances. Again, I’m very glad your dad’s friends made it but that kind of venom extractor has been determined to do more harm than good.

https://www.snakebitefoundation.org/…/the-truth-about…

19) Does it matter where on the dog dexamethasone is administered? Should it be injected at the site of the bite, or just anywhere? Dr. Jeffrey … dexamethasone is mostly considered an outdated treatment not recommended by many ER snake bite vets unless they suspect anaphylactic shock. It can actually do more harm than good in the wrong exact situation following an envenomation.

20) With regards to coral snake id, is the saying “red next to black is venom lack, red next to yellow is one dead fellow” true? Dr. Jeffrey … as a general rule east of the Mississippi it can help distinguish but if you aren’t sure I’d recommend keeping your distance. Coral snakes aren’t known for being overly defensive and are thankfully easy to avoid for the most part 👍

21) So this is slightly off, Topic but venomous spiders? Probably more common in Australia and southern us. But how much of an issue with their bites to animals? I had a friend who’s dog many many years almost died from one but not sure about current day. Dr. Jeffrey …spider bites are very hard to identify and are often just suspected possible diagnoses based on symptoms and history. Antivenom is seldom used as it has been known to cause anaphylactic reactions and the majority of spider bites are not life threatening(depending on the spider of course.) Supportive care often consists of mostly pain management but again this depends on the exact spiders found in your area.

22) I’m in the uk, my Doberman approx 2 years was playing in my dads garden, happy & playful by the bonfire pile, next day he was at a show & not himself but were weren’t unduly concerned as it was a warm day, he was still eating & drinking normally, A few days later on examination underneath him he had what appeared to be a small swelling with 2 puncture wounds. Our vets weren’t concerned as he had started to feel better in himself. 6 months later he was diagnosed with cancer, could this have been a coincidence or could being bitten triggered something in his system? I always wondered but never really got the answer.. Dr. Jeffrey …while adder bites can possibly be fatal in dogs the timeline would typically be within the first 72hrs or so after a bite. I am unaware of any documented cases of a snake bite causing cancer and some venoms have actually shown some possible promise for cancer therapy in ongoing research projects.

23) I’m in Nevada. There is a rattlesnake vaccine. How effective is the vaccine and is it worth getting? Dr. Jeffrey …efficacy is highly debatable and I would treat a vaccinated dog the same as an unvaccinated one. They may have a higher chance of surviving the bite but a lot of us aren’t convinced by the available data. Having said that I do have some high risk patients that get the vaccine after a through discussion with their humans. sidewinders aren’t found as North as Reno. Luckily they have one of the less potent venoms of the North American rattlesnakes but bites still can require medical attention. This is a good map resource for venomous snake ranges in Nevada.

http://www.ndow.org/…/Animals/Concerns/NV_Ven_rept.pdf

24) At our previous property in UK I only saw 2 grass snakes in 25 years.

Now, in France I’ve seen too many. I have 5 dogs so it’s always a concern. The bigger snakes can be defensive and, the only small one I was almost tempted to pick up turned out to be a viper which we relocated miles away. Last year we saw less snakes but more rodents. Right now this season I’m a lot more concerned with the processionary caterpillars which nest in pine trees and come down to form lines. The hairs are lethal to curious animals and I got some in my thumb which was numb for 10 months. Dr. Jeffrey …the possibly dangerous snakes in France would be the asp viper(easily confused with the harmless viperine snake,) the Montpellier snake which is very difficult to be bitten by and has a mild venom, and the common adder. There is the Orsini’s viper but it is very unfortunately almost extinct. Luckily the grass snakes are harmless if a little intimidating. The non-venomous snakes in France are typically more defensive than the venomous ones and many species look very similar.

https://wildlifeinfrance.com/snakes-france/snakes-in-france

25) We get a lot of king snakes in our back yard here in Georgia and my dogs have killed them before. Now, king snakes aren’t venomous, so I’m not worried about that, but my lab has been bitten by them before. What’s the proper care for these bites and should I always take him to the vet when it happens? So far it’s happened twice (both times I was not home and someone else was watching them since I like to go outside with them during snake season here in Georgia) and they’ve killed the culprit so I knew for sure it was a king snake. My little terrier dog flushes them out, and my lab kills them, they’re absolute menaces 😞Dr. Jeffrey …. it’s very hard to curb this behaviour as it is natural instinct for some dogs to hunt. Unfortunately I am not the best resource for behavioural modification in the canine but there may be methods of snake aversion training for non-rattlesnakes that I am unaware of. The only medical care I recommend for non-venomous snake bites is close observation and basic first aid in regards to cleaning the bite. I discourage the use of prophylactic antibiotics for ANY kind of snake bite unless I have a suspicion of a secondary infection which is an extremely rare complication.

26) When we raised cattle we would always keep injectable vitamin c as an antidote for snake bites. ( Victoria Australia). I have been told it works for dogs too. Is this correct? Of course a trip to vet is a must, but will it help before getting to the vets. ? Dr. Jeffrey …there is no evidence to support the use of vitamin C unfortunately. It is a great antioxidant though.

27) I’ve read that diphenhydramine can be given after bite while on route to vet to help slow the toxin. True? Dr. Jeffrey …diphenhydramine can help with decreasing the histamine response which can be part of a reaction to a snake bite. I would never rely on diphenhydramine alone but it can certainly help and if far away from medical aid I wouldn’t hesitate to give an appropriate dose to my own pet.

28) I am a vet tech in Florida and we just lost a favorite patient to a snake bite 🙁Owner was working her in a field and she tangled with something. He didn’t see the snake but said the dog went down fast. She fell down, got up, crapped herself and fell dog again. He scooped her up and she was dead within two minutes.She was a 50 pound Pudelpointer. No bleeding, no swelling and we couldn’t find bites (owner didn’t want us the shave her). Any idea what this would have been? He thinks it was a rattlesnake. Dr. Jeffrey …that’s interesting as it sounds like a neurotoxin rather than a destructive toxin. The most potent neurotoxin in a land snake in Florida would be a coral snake but bites are rare. Sudden death from a massive Eastern diamondback bite could be possible or maybe a cottonmouth. The suddenness of the acute death is honestly pretty surprising. Poor kiddo.

29) No venomous snakes in Madagascar . Dr. Jeffrey ….technically there are but they are rear-fanged and only mildly venomous 👍

30) I live in Minnesota and to my knowledge, we don’t have any venomous snakes here.Our rental property has a family of garden snakes that has been living under the front steps for years. Our tenants have been asked not to do anything that moves or harms the snakes – that we like them and they’re free pest control. Love our local snakes. Dr. Jeffrey …the majority of Minnesota snakes are harmless. Of the 17 snake species in the state, only two are venomous, the Timber Rattlesnake and the Eastern Massasauga. Both are found only in the southeastern counties and are rarely encountered. Thanks for encouraging responsible treatment of our wonderful native snakes.

31) I know that you said most snakes aren’t venomous and where I live there are no venomous species, but is there any concern for say mouth bacteria? Like if my dog gets bit, should I still worry about getting something antibacterial from the vet or just a home clean? Dr. Jeffrey …the bacteria in reptile mouths seldom causes an issue from bites. I always recommend gently cleaning a bite and a vet visits is always a good idea if you are concerned but giving preventative antibiotics for any snake bite(venomous or non-venomous) is no longer advised by medical communities due to the extreme rarity of secondary infections and our historic overuse of antibiotics leading to resistance.

32) I live in upstate NY region, in a very woodsy kind of region, any of these common? I know there’s signs at trails for rattle snakes. Dr. Jeffrey …here are three venomous snake species in New York: the timber rattlesnake, the massasauga (found only in the Rochester/Syracuse area) and the copperhead. All are uncommon, and the timber rattler is listed as a Threatened species in New York.

33) I live in Victoria, Australia. We have red belly blacks, tigers, eastern browns, king Browns, (king browns and the eastern browns can get cranky and chase so I would not recommend turning a hose on them) copperheads , all these are venomous and their bites requiring immediate vet care. So far I have had three emergency dashes to the vet. There is a very unfortunate old wives tale about vit C ‘curing ‘ a snake bite. It wont ‘cure’ with invenomation by Aussie snakes. Does it work with American snake bite? Dr. Jeffrey… the claim is that it’s antioxidant properties help with recovery. “Vitamin C (ascorbic acid) has long been a folk-remedy for a myriad of ailments including snakebite. As with other alternative first-aid/treatment options, there is a conspicuous lack of supporting evidence and no mechanism for its efficacy has been proposed or tested.”

34) We live in North Texas about an hour north of Dallas on 23 acres. Lots of copperheads here. We have outside dogs in a fenced in acre lot of their own next to our house. They both have been bitten on more than 1 occasion. Dr. Jeffrey ….thankfully copperhead bites are typically mild compared to some of the rattlesnake species in North America. I still recommend a vet check up if a bite is suspected as the safest option if possible but survival rates for copperhead bites are very high.

35) In our first aid kits here in Sydney, Australia we have snake bandages to help with pressure and immobilising the limb (they have shapes that tell you if it’s too tight). Can or should you use these on pets? Dr. Jeffrey …for most Australian venomous snake bites appropriately applied pressure bandaging is the current best medicine first aid recommendation. The risks of bandaging are mostly from applying them too tightly or leaving them on too long and with bites that cause a lot of painful swelling they aren’t recommended.

36) I live in Central Washington State and we have ALLOT of rattlesnakes in our area. I just heard there is a “vaccine” to help protect our pets if they are bitten. Do you know anything about that? Dr. Jeffrey…the vaccine is debatable in regards to efficacy. It was designed for western diamondback rattlesnakes and primarily use in California initially but there are claims of some cross protection for other North American crotalids. I do have certain high risk patients on it personally but I would treat them the same as an unvaccinated dog if they got bitten. Snake aversion training is great if you can find a reputable company that doesn’t harm the snakes.

37) We have copperheads, rattlesnakes, and water moccasins that we have to be on the lookout for here in NC. How bad would a water moccasins bite be to a pet? Dr. Jeffrey ….of the three snakes the copperhead bite would be of least concern but still potentially dangerous. The cottonmouth bites are not typically immediately fatal but can cause life threatening complications over the 24hrs or so after a bite.

38) Just a curiosity question. Humans now have 2 FDA approved antivenoms for treatment of all North American pit viper envenomations. Since you mentioned getting an ID for the correct antivenom, do animals not have something similar? Just snake (species?) specific antivenom? Dr. Jeffrey …depends on where you are in the world. In the US antivenom in veterinary medicine is limited to a polyvalent product for patients bitten by pit vipers (rattlesnakes, cottonmouth and copperhead snakes.) In this situation an ID on the snake helps with determining a prognosis as the fatality rates and how aggressive you need to get with treatment differs from species to species. There is no antivenom for coral snake bites in pets that is easily procured.

39) I pray this never happens again, but a summer or 2 ago my dog pounced on and tried to bite a moccasin. A rather large moccasin. His only saving grace was the snake had no idea we were there so when my dog pounced on him, he was standing on his head. My question is, is there any danger to a dog if it licks or bites the body of the snake? I know, it sounds like a stupid question but oh well. Dr. Jeffrey ….no such thing as stupid questions, no worries. There’s no danger from licking or biting the snake(besides putting themselves at risk of a bite being so close to the snake if it is venomous.) Remember that even dead venomous snakes can deliver a potentially fatal bite though if a dog is playing with a dead snake.

40) How long can a snake bite after it’s dead or does it depend on the snake? Dr. Jeffrey …risk depends on the snake and how it died. Confirming death is hard in many cases even for veterinarians that have to euthanise a snake. We often use tools like a doppler to confirm that the heart has stopped beating. In the case of a decapitated snake as an example though(I do not advocate decapitating snakes but it’s a common enough encountered scenario,) the longest recorded bite has been after 90 minutes with a rattlesnake.

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