# Are grapes/raisons really poisonous to dogs? **URL:** \ **Category:** Factual Questions\ **Created:** [January 2, 2005, 3:38am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645 "2005-01-02T03:38:13Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Roland\_Deschain](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Roland\_Deschain](https://boards.straightdope.com/u/Roland_Deschain)\ **Post date:** [January 2, 2005, 3:38am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/1 "2005-01-02T03:38:13Z")
There was an article in the Indianapolis Star about two weeks ago that warned of Holiday dangers for dogs. Among the items listed to watch out for were Macadamian nuts which supposedly can cause temporary paralysis and grapes which were said to sometimes cause kidney failure. Today, on the WIBC radio show a caller called Dr. Wosson (a vet in Zionsville who hosts the show) and asked about this issue. He said that although his wife was also a vet, neither had ever heard of this being a concern (although they are often asked the question). He promised to research the issue more and address it in next weeks show. Can anyone out there help the vet out (I will forward any replies to his email once I look it up at [www.WIBC.com](http://www.WIBC.com)). By the way how is it that animals that share so much of our DNA can have radically different sensitivities to substances harmless to us? Doesn’t this raise issues in animal research that are significant (for example maybe Vioxx is harmless in rabbits while causing us to have heart attacks). ---
**Author:** ![Skywatcher](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skywatcher/32/254_2.png) [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)\ **Post date:** [January 2, 2005, 3:50am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/2 "2005-01-02T03:50:53Z")
> [@Roland Deschain](#): > > Are grapes/raisons really poisonous to dogs? [Snopes](http://www.snopes.com/critters/crusader/raisins.asp) says they are. ---
**Author:** ![Spongemom](https://avatars.discourse-cdn.com/v4/letter/s/278dde/32.png) [@Spongemom](https://boards.straightdope.com/u/Spongemom)\ **Post date:** [January 2, 2005, 3:54am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/3 "2005-01-02T03:54:25Z")
Oh man how I wish I could answer this question. I’m halfway through my veterinary course, and so far, nothing like that has come up. My textbook doesn’t even mention it, but then again it’s more of a technical/laboratory book. I’ve always heard that you don’t want to give grapes, raisins, or chocolate to dogs, and I’ve heard the reasons, but I’m not thinking clearly enough right now to remember them well enough to post them. I don’t want to give anyone misleading advice, especially concerning animals. I stay on the safe side and avoid those foods with dogs, because there’s a million different specifically-for-dog treats out there that make them happy without taking unnecessary risks. My 2 cents. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [January 2, 2005, 4:02am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/4 "2005-01-02T04:02:22Z")
Chocolate is indeed [highly toxic](http://www.vetheart.com/choc.html) to dogs. Never heard anything about grapes, though. > [@](#): > > Chocolate contains theobromine (a compound similar to caffeine) which is poisonous to dogs. A dose of 50 mg/lb can be fatal to a dog. Milk chocolate contains 45 mg of theobromine per ounce and unsweetened baking chocolate contains 400 mg per ounce. Just one ounce of unsweetened baking chocolate can kill a small breed dog. Theobromine when ingested by dogs causes release of epinephrine (adrenaline) which causes the heart to race and serious cardiac arrhythmias to develop. Signs of chocolate poisoning in dogs include vomiting, diarrhea, excessive urination, hyperactivity followed by depression and coma, seizures, and death. ---
**Author:** ![Miabella](https://avatars.discourse-cdn.com/v4/letter/m/ccd318/32.png) [@Miabella](https://boards.straightdope.com/u/Miabella)\ **Post date:** [January 2, 2005, 5:07am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/5 "2005-01-02T05:07:39Z")
Yes, grapes and raisins can cause acute renal failure in dogs. The ASPCA Animal Poison Control Center has information about the danger of feeding [grapes or raisins](http://www.aspca.org/site/PageServer?pagename=grapes) to dogs on their website. ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [January 2, 2005, 11:45am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/6 "2005-01-02T11:45:16Z")
> [@Roland Deschain](#): > > By the way how is it that animals that share so much of our DNA can have radically different sensitivities to substances harmless to us? That works both ways, you know. For instance, while poison ivy is, well, poisonous to humans many mammals and birds eat it with no problem whatsoever. The venom of the Australian Funnel Web spider is far more toxic to humans than to most other animals. > [@](#): > > Doesn’t this raise issues in animal research that are significant (for example maybe Vioxx is harmless in rabbits while causing us to have heart attacks). Yes, it can - which is animal testing is only one step in the process. A historical example: thalidomide did not cause limb deformities in the rats and mice used to test it. It _did_ cause smaller than normal litters, but not so small it was immediately apparent to the researchers since rodent litters vary in size anyway but rather something that showed up after more analysis ---
**Author:** ![meowpossum](https://avatars.discourse-cdn.com/v4/letter/m/848f3c/32.png) [@meowpossum](https://boards.straightdope.com/u/meowpossum)\ **Post date:** [January 2, 2005, 6:47pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/7 "2005-01-02T18:47:58Z")
I’ve heard that grapes and raisins are poisonous to dogs too. It’s better to be safe than sorry, so I would **never** let my dog have anything with grapes in it now. I wouldn’t want to take a chance, no matter how small. That being said… When I was a kid, we had a 50 foot fence covered in grape vines in the back yard. The collies loved them. In the summer, you’d look out the back window and all you could see was two big brushy tails swishing back and forth under the vines as the dogs gorged themselves on purple grapes. If they ate enough of them, they’d get gawdawful diarrhea, but other than that, nothing bad seemed to happen. ---
**Author:** ![CarnalK](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnalk/32/486_2.png) [@CarnalK](https://boards.straightdope.com/u/CarnalK)\ **Post date:** [January 2, 2005, 7:05pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/8 "2005-01-02T19:05:49Z")
Well, I guess I won’t give my dog too many more grapes then 🙂 From the links it looks to be toxic at higher levels. I noticed zero ill effect when I give my dog one or two grapes. Dogs were originally carnivores so I’m not surprised eating a pound of plant material doesn’t go down right. ---
**Author:** ![NinjaChick](https://avatars.discourse-cdn.com/v4/letter/n/71c47a/32.png) [@NinjaChick](https://boards.straightdope.com/u/NinjaChick)\ **Post date:** [January 2, 2005, 7:26pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/9 "2005-01-02T19:26:09Z")
My medium-sized (about 50lbs) dog loves grapes. (Bizarre anecdote: I was sitting in the living room with my sister the other day. She had some chicken on a plate; I had a bowl of grapes. The dog was begging from _me_.) She eats small quantities of them all the time; I’ve never seen any adverse effects. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [January 2, 2005, 7:33pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/10 "2005-01-02T19:33:22Z")
I’d just like to point out that my brother has a spaniel that’s eaten what should be toxic levels of chocolate and survived with no problems. Didn’t even get an upset tummy, so it either has to be something that’s breed dependant, or dogs can build up a tolerance to the stuff. ---
**Author:** ![FilmGeek](https://avatars.discourse-cdn.com/v4/letter/f/b19c9b/32.png) [@FilmGeek](https://boards.straightdope.com/u/FilmGeek)\ **Post date:** [January 2, 2005, 10:39pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/11 "2005-01-02T22:39:46Z")
Ardred’s boss has two dogs that are positively grape addicts. They go crazy for them, especially in the summer when they get them frozen. They also love wine, but that’s another story. 🙂 This isn’t a free pass to give your dog grapes, of course, but, like most other things, some dogs can have bad reactions, some not. I had a dog who ate a box of bakers chocolate AND a bag of hershey’s kisses (he unwrapped them all) and suffered no ill effects. Doesn’t mean I let my current dog have chocolate. ---
**Author:** ![quiltguy154](https://avatars.discourse-cdn.com/v4/letter/q/ad7895/32.png) [@quiltguy154](https://boards.straightdope.com/u/quiltguy154)\ **Post date:** [January 2, 2005, 10:50pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/12 "2005-01-02T22:50:51Z")
I wonder if it’s a case of seedless vs. seeded grapes. Aren’t grapes related to apples,whose seeds contain low levels of a cyanide compound, IIRC. Might this somehow be the toxic agent How might this transfer to effects on humans? My sister-in-law has kidney problems, and her blood levels[of creatinine, calcium et al described, plus her potassium level]are elevated as well. Raisins are a favorite of hers. Any reason to give her this info? ---
**Author:** ![aerodave](https://avatars.discourse-cdn.com/v4/letter/a/f08c70/32.png) [@aerodave](https://boards.straightdope.com/u/aerodave)\ **Post date:** [January 2, 2005, 11:40pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/13 "2005-01-02T23:40:55Z")
I think a lot of the warinings against feeding cetrain foods to dogs are as much about quanitiy as they are about the substance itself. Most dogs weight much less than the average person, so bad substances come in relatively larger doses. There are lots of things that people eat of which large doses will cause problems. But in modertation, they’re okay. The problem with dogs is that a hungry dog will eat insane amounts of whatever it can get its paws on. And if that something is two pounds of grapes… So perhaps the problem is that dogs are inclined to eat more grapes than are good for them, especially if they think they taste good. It seems from the anecdotal evidence in this thread that a few won’t hurt them, but maybe some unsupervised pup somewhere ate a whole bunch. ---
**Author:** ![ivylass](https://avatars.discourse-cdn.com/v4/letter/i/9de053/32.png) [@ivylass](https://boards.straightdope.com/u/ivylass)\ **Post date:** [January 3, 2005, 12:21am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/14 "2005-01-03T00:21:47Z")
What about bananas? Our dog loves bananas, and will beg from whoever is peeling the fruit. ---
**Author:** ![Wile\_E](https://avatars.discourse-cdn.com/v4/letter/w/c37758/32.png) [@Wile\_E](https://boards.straightdope.com/u/Wile_E)\ **Post date:** [January 3, 2005, 1:25am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/15 "2005-01-03T01:25:26Z")
> [@Tuckerfan](#): > > I’d just like to point out that my brother has a spaniel that’s eaten what should be toxic levels of chocolate and survived with no problems. Didn’t even get an upset tummy, **so it either has to be something that’s breed dependant, or dogs can build up a tolerance to the stuff**. No, it’s more chocolate dependent. If it’s cheap milk chocolate that is probably more wax than actual chocolate then they may be able to eat a lot without a problem. Baker’s chocolate is the worst because it’s very concentrated. Fancier chocolates are worse than your cheaper brands. The only breed dependence would be that larger breeds can eat more chocolate before reaching a toxic does than a smaller breed dog. An animal with an existing medical problem, such as heart disease, will also be more susceptible. As for grapes/raisins. The last time I researched it they still did not know exactly why it was toxic but it is indeed toxic. At my clinic we saw at least one suspected case of this. We’ve seen a few macadamia toxicities (small dogs only) and lots and lots of chocolate calls. We actually keep a tally of how many calls we get about chocolate around chocolate the related holidays (Valentines, Easter, Halloween and Christmas). ---
**Author:** ![vetbridge](https://avatars.discourse-cdn.com/v4/letter/v/b5e925/32.png) [@vetbridge](https://boards.straightdope.com/u/vetbridge)\ **Post date:** [January 3, 2005, 3:03am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/16 "2005-01-03T03:03:07Z")
In 15 years of practice I have seen a single case of raisin induced acute renal failure in a dog. Of course, the first I’d ever heard it mentioned was five or six years ago, so I may have missed one or two. Chocolate seems to be one everybody knows. Never seen a chocolate covered raisin case. 😉 The same with cats and Tylenol (acetaminophen). The most common toxicity I see currently is folks trying to de-flea their cats cheaply with OTC dog flea products. Many of them die. ---
**Author:** ![vetbridge](https://avatars.discourse-cdn.com/v4/letter/v/b5e925/32.png) [@vetbridge](https://boards.straightdope.com/u/vetbridge)\ **Post date:** [January 3, 2005, 3:12am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/17 "2005-01-03T03:12:52Z")
> [@vetbridge](#): > > The same with cats and Tylenol (acetaminophen). What I meant was that most people know that Tylenol is toxic in felines. Actually a fun toxicity to treat. The other toxin I see a sh\*tload of this time of year is ethylene glycol (antifreeze for cars). ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [January 3, 2005, 3:17am UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/18 "2005-01-03T03:17:56Z")
Can cats be injured by raisins? A few weeks ago I discovered that one of our cats likes them…I’d hate to make him sick, though. ---
**Author:** ![vetbridge](https://avatars.discourse-cdn.com/v4/letter/v/b5e925/32.png) [@vetbridge](https://boards.straightdope.com/u/vetbridge)\ **Post date:** [January 3, 2005, 2:19pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/19 "2005-01-03T14:19:34Z")
> [@elfkin477](#): > > Can cats be injured by raisins? A few weeks ago I discovered that one of our cats likes them…I’d hate to make him sick, though. I have never heard of renal failure in a cat due to grapes/raisins, however cats are obligate carnivores and are unlikely to ingest grapes. I would avoid them as the toxic principle remains unknown. From the ASPCA’s veterinary toxicology pages: > **[ASPCA](https://www.aspca.org/?pagename=grapes)** > > Learn more about the ASPCA's work to rescue animals from abuse, pass humane laws and share resources with shelters nationwide. Join our fight today! > [@](#): > > Even though the exact cause of the renal failure is unknown, dogs who ingest grapes and raisins can be treated successfully to prevent its development. ---
**Author:** ![Arwin](https://avatars.discourse-cdn.com/v4/letter/a/51bf81/32.png) [@Arwin](https://boards.straightdope.com/u/Arwin)\ **Post date:** [January 3, 2005, 4:01pm UTC](https://boards.straightdope.com/t/are-grapes-raisons-really-poisonous-to-dogs/282645/20 "2005-01-03T16:01:30Z")
> [@elfkin477](#): > > Can cats be injured by raisins? A few weeks ago I discovered that one of our cats likes them…I’d hate to make him sick, though. I don’t think so … the cat of a friend of mine likes them and he seems fine. But then, too much of a good thing … 😉