Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Thiamine Deficiency in Dogs: 7 Signs to Look For (Vet Answer)

bottle of vitamin b thiamine

Vitamins are essential to the overall health of people: they help fight infections, metabolize food, heal wounds, and regulate hormones. But what about their role in dogs? Though not often spoken of, they are just as important in our canine friends. This article will focus on Vitamin B1, also known as thiamine. Inadequate thiamine in the body, termed thiamine deficiency, can cause serious neurological issues in dogs.

This article will delve into thiamine deficiency—what it is and what causes it, but, just as importantly, what signs you should be looking out for.

divider single dog paw oct 2024

What is Thiamine?

Thiamine is a water-soluble vitamin that plays a crucial role in carbohydrate metabolism. Carbohydrates are a macronutrient that provide energy and other health benefits. In dogs, they are also the main source of dietary fiber. Dogs are not able to synthesize thiamine. This means that it must be obtained from the diet. Most dogs fed a commercial or store-bought pet food will receive adequate dietary thiamine, and, therefore, are very unlikely to develop thiamine deficiency.

Vitamin B1 thiamine capsule illustration
Image By: Maxx Studio, Shutterstock

What Causes Thiamine Deficiency?

Vets recognize four main causes of thiamine deficiency in dogs:
  • Dogs fed a diet without enough thiamine, such as vegetarian diets.
  • Dogs fed raw fish or shellfish diets. These foods contain enzymes that break down thiamine in the body.
  • Dogs fed overly-heated food. Thiamine is heat-sensitive, so is easily destroyed when food is cooked.
  • Dogs fed treats or diets preserved with Sulphur dioxide.

divider dog paws oct 2024

Signs to Watch for

Thiamine deficiency can occur in any breed of dog, at any age. Most of the signs of thiamine deficiency in dogs are attributed to the forebrain. Below are the seven most common signs of thiamine deficiency:

1. Lethargy

Of course, lethargy is seen with a vast number of diseases in dogs, not only thiamine deficiency. Reduced energy levels and a dull or quiet demeanor are early signs of thiamine deficiency.

Lethargic
Image Credit By: Mylene2401, Pixabay

2. Reduced Appetite

This is similar to lethargy—as dogs don’t feel well, they become less interested in eating. This also occurs relatively early with thiamine deficiency. Loss of appetite can be seen with a number of health issues in dogs.


3. Weight Loss

Weight loss occurs days to weeks after thiamine deficiency first develops. This is due to reduced absorption of carbohydrates (energy), decreased food intake (loss of appetite), and increased basal energy expenditure.


3. Vomiting and Diarrhea

Vomiting and diarrhea are non-specific gastrointestinal signs in dogs with thiamine deficiency. Usually, the vomiting and diarrhea are not severe, but “wax and wane”, and fail to resolve without increasing thiamine intake.

Black dog vomiting
Image By: Mumemories, Shutterstock

4. Weakness

Weight loss and reduced muscle mass will lead to weakness in dogs with thiamine deficiency. Thiamine also plays a role in the conduction of nerves through the body, which tells the muscles what to do. Without this, muscle function also becomes impaired. More specifically, weakness appears as the inability to walk or support weight and muscle tremors.


5. Seizures

Seizures occur when thiamine deficiency has been present for a long time, indicating that the problem has become severe. Seizures occur when the function of the brain (in particular, the forebrain) has become impaired. Seizures appear as loss of consciousness, with alternating stiffening and jerking of the legs, and often urination/defecation.


6. Coma

Coma is life-threatening. This is seen with the most severe and untreated cases of thiamine deficiency in dogs. Coma is a prolonged period of unconsciousness and can lead to death.

Is your dog presenting any of these signs? Talk with one of our experts here:

Did you know you can talk to a vet online? Click on the image or button below to schedule a call: PangoVet_Mention-in-Content Savings V1


divider dog paws 3 oct 2024

Summary

Thiamine deficiency is rare in dogs. Its occurrence can be prevented by feeding commercial dog foods with adequate thiamine and avoiding raw-fish diets. If you are unsure if your dog’s diet has enough thiamine, don’t hesitate to contact a veterinarian or pet nutritionist.

Although the early signs of thiamine deficiency are mild and not life-threatening, the neurological signs that occur later in the disease process are very concerning. This emphasizes the importance of seeking veterinary help early—as soon as you notice that your dog is unwell. Most cases can be diagnosed early based on dietary history, physical examination findings, and blood tests.


Featured Image Credit: luchschenF, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

12 Best Emotional Support Dog Breeds: Descriptions & Traits (With Info & Pictures)

It is not just in modern times that people have been turning to animals for companionship and emotional support. People from all walks...

Can Dogs Recognize Faces? What Science Says

We know that dogs have an excellent sense of smell and can identify their favorite people by their scents, but do dogs also...

Chocolate Labrador Dog Breed: Info, Pictures, History & Traits

A chocolate Labrador is a particular color of the Labrador Retriever. These dogs are known for being very friendly and outgoing. They’re one...

International Pooper Scooper Week 2025: What Is It? Here’s How to Celebrate

International Pooper Scooper Week was established by The Association of Professional Animal Waste Specialists to help spread awareness of the importance of picking...

More related

Why Doesn’t My Dog Like Toys? 6 Vet-Reviewed Reasons & Suggestions

You may feel a bit envious when you look out your window and see your neighbor playing fetch with their dog. Nothing is...

Are Dogs Allowed on Daytona Beach? The Surprising Answer!

Daytona Beach is one of the most popular tourist destinations in the country, and with so much to do and see there, it’s...

15 Pet Food Delivery Service Trends & Statistics to Know in 2025

Pet food delivery is a vibrant and growing portion of the pet food market. More and more people are opting to buy their...

6 DIY Dog Puzzles to Mentally Stimulate Your Pup (With Pictures)

Playtime with your dog does not need to involve leaving your house. Today, more dog owners are finding safe and creative ways to...

Keep reading

Can Dogs Eat Relish? Vet-Reviewed Facts & FAQ

Most dogs are not picky when it comes to what they are eating. They’ll scarf down almost anything that a human companion offers them, and they love rummaging through the garbage for scraps or snatching a piece of food found...

Can Dogs Eat Relish

10 Best Dog Foods for Dachshunds in 2025 – Reviews & Top Picks

With their short legs and long backs, Dachshunds are among the most recognizable breeds in the world. Their sausage shape gives them the adorable moniker “wiener dogs”, and they’re a popular small breed for pet owners of all kinds. Because...

dachshund dog eating from elevated bowl

Can Dogs Eat Papaya? Vet-Verified Facts & FAQ

On a hot summer’s day, there is nothing more refreshing than eating a variety of fruit. One delicious fruit is the papaya! Of course, as a dog parent, you don’t want your furry friend to miss out on the fun....

Can Dogs Eat Papaya

Blue Buffalo Dog Food Review 2025: Pros, Cons & Verdict

Review Summary Blue Buffalo is one of the largest dog food manufacturers in the United States, and its surge to the top is because it creates high-quality and nutritious food for dogs. It makes all its food in the United...

Dogster_Blue Buffalo Dog Food Review

Can Dogs Eat Cream of Wheat? Vet-Approved Nutrition Facts & FAQ

The grain-free diet craze is dying down among pet owners, leading some to wonder if dogs can eat grain products like Cream of Wheat. While it’s best to avoid table food for your dog and stick to a balanced commercial...

Can Dogs Eat Cream of Wheat

5 Safe Chews for Dogs: How to Choose the Right Dog Chews (Vet Approved)

No one would argue that dogs love to chew! It seems to be one of their favorite daily activities. Since it’s something that they do so frequently, you may think that they have an iron stomach and can chew up...

Golden Retriever holding a chew

Can Dogs With Pancreatitis Eat Eggs? Vet-Approved Facts & FAQ

Pancreatitis is one illness you want to take seriously, as mismanaging this disease can quickly become fatal. Pancreatitis is the inflammation of the pancreas, the part of your dog’s body that creates hormones such as insulin and digestive enzymes. The...

Can Dogs With Pancreatitis Eat Eggs

10 Best Chicken & Rice Dog Foods in 2025 – Reviews & Top Picks

Chicken and rice recipes are among the most popular and common dog food formulas. Virtually every brand and formula offers a chicken and rice recipe, and for good reason! Chicken is a lean, healthy, complete protein that’s affordable and highly...

cream dog eating from the bowl