What Are the Symptoms of Vitamin D Toxicity in Dogs?

Vitamin D is an essential vitamin, working to maintain the balance of calcium in the body. Calcium helps the function of the heart, muscles, and nerves, as well as bones.

Unfortunately, too much vitamin D can also cause problems—for more than just humans. It’s easy enough for humans to avoid taking in way too much vitamin D, but our pets are another matter entirely. Vitamin D toxicity is a serious risk for dogs, and can happen through the ingestion of certain human medications, rodenticides that use vitamin D, tainted dog food, or poorly-balanced diets.

How Can Vitamin D Toxicity Occur?

In dogs, one of the most common sources of vitamin D toxicity is the accidental ingestion of certain rodenticides, including Muritan, Mouse-B-Gone, Rampage Rat, and other rodenticides containing vitamin D.

In some cases, dogs may ingest a dangerous amount of vitamin D by accidentally eating certain medications meant for their humans, or even by ingesting vitamin D supplements. In rare cases, dog foods may be tainted excessively with the vitamin, or their diet may have very high concentrations of liver, milk, fatty fish, or eggs, leading to high vitamin D intake. Any of these things can lead to an imbalance of calcium and phosphorus, which can in turn become deadly.

What Symptoms Should I Look Out For?

What should you look out for as signs that your dog has ingested toxic amounts of vitamin D? There are a few major signs to look out for.

Initial signs that your dog might be suffering from vitamin D poisoning can appear between 8 and 48 hours after ingestion. These signs include:

• Weakness
• Loss of appetite

After these signs, you may observe:

• Vomiting
• Increased drinking and urination
• Constipation
• Dehydration

In the most severe cases of vitamin D poisoning, signs include:

• Dark, tar-like stools (indicates bleeding in the gut
• Difficult breathing (indicates bleeding in the lungs)

Other things to look out for include a slow heart rate or abnormal heart rhythm. If your dog is showing any of these signs, contact your veterinarian as soon as you can, the U.S. Food and Drug Administration (FDA) urges.

What is the Treatment for Vitamin D Poisoning?

As with many health conditions, the treatment for vitamin D poisoning will depend on how long it has been after ingestion and how far your dog’s symptoms have progressed. If the problem is caught within six hours of ingestion, your dog will undergo something called gastrointestinal decontamination using activated charcoal and meant to induce vomiting in order to rid the body of the problem.

After this six-hour window, certain medications may be used to block the absorption of calcium, and in turn increase the level of calcium excretion through urination, eventually bringing calcium levels back down to safe levels.

What Dog Foods Are Linked With Vitamin D Poisoning?

Hill’s Pet Nutrition announced a recall
of a slew of its Prescription Diet and Science Diet canned dog food products in January of this year due to excessive amounts of vitamin D that placed pets at risk. A full list of the products affected can be found on the company’s recall webpage.

Join a Free Hill’s Pet Nutrition Dog Food Recall Class Action Lawsuit Investigation

If you purchased Hill’s Science Diet or Prescription Diet canned dog food, you may qualify to join this Hill’s dog food recall class action lawsuit investigation.

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