29 March 2016

How Much Vitamin D Is Toxic to Dogs.

My dog just ate a vitamin D capsule is this dangerous?  Should I be concerned? My dog ingested my vitamin D3 supplement, what should I do about it? Should I take my dog to the vet? Is this poisonous? These are the sorts of questions which vets are often asked in relation to D group vitamins.


vitamin D toxicity dog
Not all vitamins are safe, vitamin D toxicity is possible in the dog.

Most of the cases I have been involved with related to vitamin toxicity in dogs has involved vitamin D or D group vitamins. Dogs commonly get access to these where owners have left supplements lying about the house, however vitamin D toxicity can also occur where dogs have access to rodent poisons.

1. But how much vitamin D is toxic to dogs? : Well opinion varies depending on where you look up the information and this will also vary with individual cases but taking a very careful and conservative approach I usually start to become concerned at dose rates higher than 0.1 mg per kg of the dog's bodyweight. { There are 40,000 iu per mg of vitamin D }

Lets express the above in a easier to understand way. Basically you will start to be concerned when a dog takes more than  4,000 iu per kg of bodyweight { = 1,811 iu per pound of bodyweight }

To be fair most cases of vitamin D toxicity that I have dealt with involved much greater amounts than that which I have listed above but where I am advising owners I would very much doubt if the dog concerned will experience any problems of any sort where lesser amounts than those I stated were swallowed.


2. What are the symptoms of vitamin D toxicity? : Vitamin D is potentially toxic to dogs because it is linked with the metabolism of calcium in the body. Too much vitamin D causes too much calcium (hypercalcemia), and that is what causes the damage, this could include kidney failure, haemorrhage, and tissue mineralization in the heart, liver and kidneys.

Where your dog is in an overdose situation you might expect to see symptoms start some 12 - 48 hours after ingestions and these could include vomiting, dark diarrhoea containing blood, lethargy, inappetance and drooling in the early stages. Later symptoms could include marked weight loss and seizures. Fatalities are possible where very large amounts have been ingested.


3. What to do if you suspect your dog has taken an overdose? : As with a great many toxins if you can induce vomiting to recover the drug within the first hour after ingestion { Two hours at the very outside } then things should be OK. A commonly used way to induce vomiting in the dog is with 3% hydrogen peroxide { Not hair colouring peroxide } A usual oral dose is one teaspoon { 5 ml } per 10 pounds of body weight. Vomiting should occur within 15 to 20 minutes but if no vomiting occurs, you can safely repeat the process a second time.

But if you fail to induce vomiting and / or clinical signs develop then you will need your vet involved ASAP as supportive care such as IV fluids may be necessary and some dogs may require a blood transfusion. There are drugs which can be used to prevent further absorption of the ingested vitamin D if given early enough.


So the bottom line is that if you suspect your dog may have taken a D group vitamin overdose and you are in any doubt then you should take your dog to an ER vet as soon as possible. Better safe than sorry ....