Vitamin D Toxicity in Dogs

If you are looking for information about vitamin D toxicity in dogs, you will find my article today very helpful. The most common source of vitamin D poisoning in pooches results from chemicals used to kill rodents. However, if your dog eats food with a lot of vitamin D or uses drugs with too much of this content it also might lead to toxicity. Puppies and young dogs are at a greater risk of having vitamin D toxicity than those in other life stages.

A fat-soluble vitamin, Vitamin D is a vital nutrient in your dog’s diet that helps your pooch control the balance and maintenance of normal levels of phosphorous and calcium in their body. Calcium is vital in making your dog’s bones and muscles strong to support healthy living. Unlike us as dog owners, our dogs can’t absorb vitamin D from sunlight which is why it is included in their diet.

Today, we shall look into the causes, diagnosis, and treatment of vitamin D toxicity and more. We also have tried to answer all the questions you might have regarding this topic. 

What Causes Vitamin D toxicity in Dogs

If your dog eats dog food that contains high levels of vitamin D, that could lead to toxicity and so will when he eats your vitamin D supplements accidentally. Another common cause of this kind of poisoning is the accidental consumption of chemicals like cholecalciferol (vitamin D3). This is a chemical that is intended to exterminate rodents such as mice and rats.

Even as little as 0.1 milligrams per kg dose can lead to vitamin D poisoning which translates to approximately 0.45 mg/10 lbs. of body mass. However, 2 mg/kg is considered a lethal dose as it equates to approx. 9 mg/10 lbs. dog body weight.

What are the Symptoms of Vitamin D toxicity in Dogs?

When your dog contracts vitamin D toxicity, may show symptoms such as vomiting, drinking, little appetite, urinating, excessive drooling, obesity, or loss of weight. Depending on the vitamin D concentration in your dog’s diet, food-linked toxicity tends to grow slowly over time. If your doggie gets vitamin D poisoning via supplements or rodenticide, he will start showing these symptoms of sickness in a few hours or days.

In case you think that your pooch is revealing the symptoms of toxicity mentioned above, make sure that you take him or her to your vet straight away. Other symptoms include constipation, blood in vomit, seizures, and abdominal pain.

How to test Vitamin D toxicity in Dogs

The best and only way to test your dog for vitamin D toxicity is by taking him or her to your vet for diagnosis. What your vet does is that he or she evaluates the signs of vitamin D toxicity in your pooch. Like your doctor, they will enquire about your doggie’s diet as well as what he might have bumped into.

As part of the testing process, your vet may take blood samples from your dog so they can check it for calcium, vitamin D, or calcium levels. In addition, he can take your dog’s urine to evaluate his kidney function. Based on your vet’s obtained results, she or he understands the most reliable course of action.

How to treat Vitamin D toxicity in Dogs

As with any other disease, the best way to treat your dog’s vitamin D toxicity depends on your vet’s assessment of the tests mentioned above. The objective, however, is to eliminate the cause of vitamin D to help prevent more exposure to the culprit. A good example for removing the cause of this toxicity is withdrawing recalled dog food found with this problem. This, in turn, will help cleanse the excess levels of vitamin D.

If your dog’s vitamin D toxicity is determined earlier when the toxicity is less critical, your vet may recommend that you change your pooch’s diet. This food elimination method can help resolve this toxicity problem in weeks or months. On the other hand, your vet may opt for prescribed medication or prolong phosphorous and calcium check-ups in your dog’s blood. This monitoring can continue until your dog’s calcium and phosphorous levels return to normal.

Can vitamin D harm a Dog?

Your doggie friend needs vitamin D as it supports many aspects of his or her optimal health, but it can be harmful if consumed at high levels. The most reliable sources of vitamin D for your dog include red meat, egg yolks, fortified food like some breakfast cereals, and liver. In addition, oily fish like salmon, mackerel, sardines, and herring are good sources of vitamin D.

Are you wondering what to do if your dog eats a bottle of vitamin D? Typically, the medication for vitamin D toxicity depends on how long it takes before you know that your dog has eaten the pills. Typically, it takes 8-48 hours for clinical signs to show after ingestion of a bottle of vitamin D. However, your vet can carry out digestive decontamination if you know about the intake within 6 hours. According to a VCA Hospitals article, this decontamination process includes provoking vomiting as well as administering activated charcoal.

Vitamin D Deficiency in Dogs Symptoms

In dogs, vitamin D deficiency exhibits symptoms such as lethargy, depression, too much drooling, joint problems, excessive thirst, and weight loss. Also known as hypovitaminosis D, vitamin D deficiency refers to insufficient levels of vitamin D nutrients in your dog’s body. If your dog suffers from this problem, he or she is susceptible to congestive heart failure. Besides, dogs are prone to increased risk for complications due to heart disease and bone softening (osteomalacia), and deformities (rickets).

To increase vitamin D in your dog, feed him or her diets containing healthy dairy products, fish, liver, beef, and fish. This makes their bones strong thus giving your dog a healthy and happy life.

How much vitamin D is toxic to a dog?

Even as little as 0.1 milligrams per kg dose can lead to vitamin D toxicity which translates to approximately 0.45 mg/10 lbs. of body mass. However, 2 mg/kg is considered a lethal dose as it equates to approx. 9 mg/10 lbs. dog body weight.

Beware of dog foods that contain high levels of vitamin D to make sure that your canine buddy remains healthy and happy. Always check at the label of the dog food you are purchasing to check that the brand is using sufficient amounts of vitamin D to prevent toxicity. 

Vitamin D poisoning dog food

As stated above, vitamin D toxicity can result from the dog food you feed your pooch if included in large amounts. Many dog foods are prepared to meet AAFCO’s minimum nutrient requirements with good vitamin D sources. Yet, your dog may have health problems in the gut that may hinder the capacity to absorb this nutrient fully leading to poisoning.

However, it is worth noting that although most dog foods meet AAFCO standards, the formulas may not meet your dog’s optimal vitamin D requirements. After all, our canine friends are unique with different abilities to take in and consume nutrients such as vitamin D.

Dog food recall vitamin D

The US Food and Drug Administration (FDA) has been busy tracking reports on vitamin D toxicity in dogs that eat dry and canned (wet) foods from certain brands. Since November 2018, the agency has released recall notifications on several dog food brands over vitamin D toxicity after reports from dog owners. The brands include Sunshine Mills Inc., King Soopers, Natural Life Pet Products, Kroger, ANF Inc., Nutrisca, Lidl, and Ahold Delhaize.

The FDA announced the recalls after testing dog food samples that exhibited too much vitamin D which was potentially poisonous. Food tests started with Nutrisca, and the rest followed. Hill’s Pet Nutrition was not an exemption as well since they recalled their canned dog food variety via a press release at the end of January 2019. You are warned to stop feeding these dog foods that the FDA has recalled. The agency also asks dog owners to report any cases of potential vitamin D toxicity to them. You can read more on the recalls on the FDA website here.

Vitamin D for dogs dosage

Minimal info about the optimal vitamin D levels in dogs, especially mature ones, and no studies on this topic are conclusive yet. Typically, dosage for vitamin D follows suit in the lack of ideal measurements. You can, however, read more about this research on the NCBI official website here.

The recovery of vitamin D toxicity in dogs or prognosis depends on whether you looking for the treatment and when. Should the medication be done earlier, the prognosis is excellent. However, this requires prolonged monitoring for proper recovery as well as dog outpatient care visits. This will ensure that your canine buddy remains hale and hearty. 

Are vitamin D3 toxic to dogs?

Vitamin D3 is very toxic when your doggie consumes it in large amounts despite being a vital nutrient in their body. Signs of vitamin D3 (also labeled as D2, calcipotriene, or cholecalciferol) toxicity are visible in doses as low as 0.1 mg per kg with 2 mg per kg being a lethal dose for a mature dog at the lowest levels.


Overall, your pooch needs vitamin D for healthy living just like we do as humans. The nutrient is usually found in food as a fortifying ingredient but is also available in some foods. Your pooch benefits from vitamin D2 (from plants) and D3 (created in the skin from sun exposure). All the recognized organizations that check on pet food quality classify vitamin D as a vital nutrient for your dog. To boost your dog’s body health, feed him recommended supplements that are rich in this nutrient such as fish, eggs, liver, yogurt, and more.