Hypothyroidism is caused when the thyroid glands do not produce a sufficient amount of thyroxine, an important hormone that converts food into fuel. Thyroid gland, which is responsible for its production, is situated in the neck.
It is one of the most important glands in the body. It is located near the trachea and has two lobes.
The gland is controlled and managed by the pituitary gland and is an autoimmune disease. In this condition, the immune system causes the thyroid to produce a less amount of thyroxine, which disrupts a number of bodily functions.
It is a common disease in dogs and affects all breeds. However, some breeds are more prone to this condition than others. These breeds include Doberman Pinscher, Irish Setter, Golden Retriever, Labrador Retriever, Dachshund, Cocker Spaniel, Miniature Schnauzer, and Boxer.
It could be due to a number of reasons and it is a manageable condition. Know all about the disease, its symptoms, diagnosis, and treatment in the blog.
Hypothyroidism Definition - What is Hypothyroidism?
Probably the most common disease in dogs, hypothyroidism is characterized by the disorder of the glands. It happens when the dog’s endocrine glands, the thyroid gland precisely, do not secrete enough T4 hormone.
This interferes with the normal working of the dog’s metabolism. Hypothyroidism can happen in the following ways.
Primary Hypothyroidism - it happens due to an autoimmune reaction of the dog’s body. In it, the body’s immune system mistakes the thyroid gland as a foreign body. As a result, it attacks it and hinders its proper and normal working.
The immune system produces antibodies that attack the gland. This causes secondary scarring of the glands’ tissues and reduces their hormone secretion.
About 90% of dogs having hypothyroidism is due to the body’s autoimmune reaction.
Secondary Hypothyroidism - when the hypothalamus-pituitary-thyroid axis does not work properly, the thyroid gland does not receive the right signals. It begins with the hypothalamus not producing a sufficient amount of thyrotropin-releasing hormone (TRH).
Due to this, the pituitary gland does not get the right orders and secrete an inadequate amount of thyroid-stimulating hormone (TSH).
This does not mean that the thyroid is not working properly, it means that it is not getting the right signals or instructions.
What is Congenital Hypothyroidism in Dogs?
‘Are hypothyroidism and congenital hypothyroidism the same?’
In a way yes, both of the conditions are the same. The only difference is that dogs develop hypothyroidism later in life, adulthood, while congenital hypothyroidism is a by-birth defect in puppies.
It is a workable medical condition that happens due to the puppy’s inherent inability to produce thyroxine. Puppies having this condition are lethargic, overweight, and a distinct ‘tragic’ kind of facial expression.
The expression is due to the water retention in the facial lobes. Apart from these, other visible characteristics include abdominal hair loss and goiter, an enlarged thyroid gland.
Puppies having this condition could suffer from the dwarfism of long bones and spines and late mental development. It is an incurable condition that could be managed with thyroxine supplements.
In case the condition is left untreated, the puppy could end up in the condition of myxedema coma that could result in the puppy’s death. Early diagnosis and treatment could prevent it easily.
Signs and Symptoms of Hypothyroidism in Dogs
The early signs and symptoms of the condition could be difficult to diagnose. The thyroid hormone levels affect nearly all of the cells of the body.
This is why dogs having hypothyroidism could show several signs of bodily dysfunctions.
The signs of thyroid disease are very subtle and at first, they are easy to miss and neglect. Some common and classic symptoms and clinical signs of hypothyroidism include the following.
Hair or Fur Loss - hair loss happens over the trunk, legs, and head of the dog. The hair loss begins at the tail and gives it a ‘rat tail’ appearance. The collar area may also have baldness or bald patches.
Skin Problems - since the skin is the most visible body organ, the first signs of hypothyroidism are visible on it. The skin gets oily, darkened, flaky, and thickened.
Due to these molds of skin, the dog would have a constant ‘distinct’ expression. The skin may also have excessive dandruff and dark patches on the skin.
Dry and Dull Coat - the hair of the coat becomes brittle and fragile. This lessens the density of the coat and leaves a puppy-like short and soft undercoat.
Ear Infections - the dog may have reddened, smelly, and painful ears, and a number of other ear infections.
Weight Gain - the dog experiences unexplained and excessive weight gain. Moreover, he is not able to lose that excess weight.
Lethargy - the dog experiences a low level of activity, and he would often be restless, easily tired, and excessive sleep periods.
Low Tolerance of Cold - the dog will be cold and have less tolerance for it. He would try to sneak into warmer places and spots.
Anemia - and this could also be the reason the dogs having hypothyroidism could not withstand cold.
High Level of Cholesterol - dogs suffering from hypothyroidism often have a high level of cholesterol in their bloodstream. This leads to obesity and because such dogs could not work out like other dogs, the condition persists.
Early Symptoms of Hypothyroidism in Dogs
Below are some early signs of hypothyroidism in dogs.
Change in Behavior
These are some early signs and being quite subtle, many dog owners ignore them.
- Irritable mood
- Several phobias
Many dog owners assume that these are just behavioral issues. If your dog has any symptoms, get him checked for hypothyroidism.
Other Subtle Signs
- Delayed wound healing process
- Poor immune system
- Dry and color-changing coat
- Seizures and tremors
Secondary Health Issues
Hypothyroidism is an underlying issue and there could be a number of other diseases and health issues due to it. Following are some common and seemingly negligible symptoms of low thyroid function in dogs.
- Neurological problems
- Joint and bone conditions
- Repeated injuries
- Acid reflux or regurgitation
- Dry cough
- Leaky gut
- Acquired laryngeal paralysis
- Eye infections and diseases
- Premature aging, vision, and hearing loss
- Heart problems
- Pancreas-related problems
- Fluctuations in blood sugar levels
- REM Behavior Disorder
- Other autoimmune diseases; Addison’s, diabetes, IBS
In case your dog has any such health problems, it is a good idea to get blood tests for hypothyroidism.
Did you Know?
Due to trivial symptoms, many vets do not agree to do the thyroid test of the dog. If your vet also refuses then ask him to draw the blood and send the sample to Hemopet or any other canine blood bank for the testing.
The cost of the testing is between $50 to $150.
What are the Causes of Hypothyroidism in Dogs?
In about 95% of dogs, the condition happens due to the destruction of the thyroid glands. This destruction could be due to lymphocytic thyroiditis or idiopathic thyroid gland atrophy. Other than these, some other conditions and causes could also contribute to the condition.
Below are some external factors that could cause hypothyroidism in dogs.
Vaccinations, Medications, and Some Foods
Besides hereditary, external factors like some kinds of medicines and vaccines could also cause the condition. Ironically, vaccinations could be the reason for a number of autoimmune diseases.
Vaccines may contain heavy metals and other elements that could be harmful to the dog. Combination vaccines and some commercial dog foods also cause hypothyroidism in dogs. All of these things take a toll on the dog’s health and immune system and cause several health problems.
Pesticides and Herbicides
People use pesticides and herbicides to get rid of unwanted pests and vegetation. Unfortunately, these contain harmful chemicals, and they contaminate everything around us; food, air, and water.
This interferes with the normal working of the thyroid gland and disrupts its functioning. Some weed killers are known for affecting the thyroid and Hpt axis.
Dog Chains, Chokes, and Collars
Dog chokes, collars, and chains could do permanent damage to the dog’s thyroid glands. Most of the dog collars are inflexible and if the dog exerts sudden pressure on the collar then it could cause damage to the neck, trachea, and thyroid glands.
To make sure that nothing like this happens, use a harness or a martingale collar for the dog. Also, make sure that the harness does not sit on the neck of the dog but on his chest.
As per the research, many environmental toxins also cause hypothyroidism in dogs. Some common reasons behind it are given below:
- Increased level of estrogen due to pesticides and plastic
- Electromagnetic waves and frequencies
- Heavy metals
- Excess fluoride in drinking water
Apart from these, any kind of toxins and environmental chemicals could disrupt your dog’s endocrine and pituitary glands’ functioning. Some of such chemicals or environmental toxins are listed below.
- BPA (bisphenol-A)
- PCBs (polychlorinated biphenyls)
Some of these things are hard to avoid but you can minimize the usage of pesticides and herbicides, and feed your dog homemade dog food to avoid pest and preservative-filled food.
Diagnosis of Hypothyroidism - How to Diagnose Hypothyroidism in Dogs?
‘How to test for hypothyroidism in dogs?’
There are a number of tests that the vet may run to check your dog for hypothyroidism. The right diagnosis makes a lot of difference and will help in starting the treatment when the disease is still in the start.
Usually, the vets rely on T4 test results and diagnose the diseases based on them. However, T4 alone is not enough and you will need to get other tests also to properly diagnose the condition.
In many cases, T4 is considered the gold standard for diagnosing hypothyroidism in dogs but it is not enough because:
- Many times, it over-diagnoses the condition
- It does not detect and identify autoimmune thyroid
As per the holistic vets, a full thyroid panel is recommended for the correct diagnosis of the condition. Below tests are included in it.
- Total T4 – Total amount of T4, thyroxine, a hormone in the blood.
- Free T4 – Free T4 level that signals the pituitary gland to produce more hormone.
- Total T3 – the total amount of bound and unbound T3 circulating in the bloodstream. Serum T3 alone is not enough for the diagnosis since most of the time, it could be influenced by some other illness that is not related to the thyroid.
- Free T3 – it also signals the pituitary gland about the production of TSH.
- Canine Thyroglobulin Autoantibody (TgAA) – dogs having autoimmune thyroiditis or hypothyroidism will have an increased amount of TgAA in their bloodstream.
If you are getting the tests done from Hemapet then you should know that they have added a new T4:Free T4 ratio into their measurement or testing protocol.
This helps in differentiating and recognizing between and thyroid disorder and any other disease or condition.
You can also contact the College of Veterinary Medicine at MSU to know about the testing protocols.
Treatment of Hypothyroidism - How to Treat Hypothyroidism in Dogs?
Hypothyroidism is not curable but it could be managed with proper medication, diet, and lifestyle. The vet would put your dog on a thyroid hormone replacement supplement or medication to manage its secretion.
It is not life-threatening but it is inexpensive and easy to treat and manage. You will have to administer oral medication to your dog for the rest of its life.
‘What is the medication for hypothyroidism in dogs?’
The drug that is used to treat the condition is a synthetic hormone, levothyroxine or L-thyroxine. The dose of the medicine depends on the severity of the condition and the size of the dog.
However, this drug may not be suitable for all dogs and some may exhibit side effects like:
- Loss of appetite
- Skin infections and issues
- Excessive thirst
- Excessive urination
A less common but possible side effect is that the dog could also develop a condition, thyrotoxicosis. It happens when the dose of thyroxine is high or the dog already has an underlying illness.
Below are the signs of thyrotoxicosis.
- Nervousness and giddiness
- Increased activity
- Increased pulse and heart rate
- Excessive drinking and peeing
- Weight loss
If your dog shows any such signs then take him to the vet immediately.
Natural Treatment for Treating Hypothyroidism in Dogs
Besides conventional medicine, natural medications and supplements also work to help your dog. However, you should avoid administering the medication yourself.
Consult a herbalist, a homeopathic professional, or a holistic veterinarian to help you chalk out the treatment plan for your dog.
Below are some common natural treatment options.
1. Natural herbs will help in maintaining your dog’s health and supporting the thyroid and his immune system.
- Coleus forskohlii (Forskolin)
- Schisandra Berry
The dosage for these herbs will be according to your dog’s need and you should consult a professional for it.
2. Homeopathic medicine and treatment methods will help in minimizing the effects of thyroiditis in dogs.
3. Using nutraceutical and glandular supplements including selenium, zinc, and iodine will support your dog’s thyroid health.
4. Trying Traditional Chinese Veterinary Medicine (TCVM) will help in identifying and balancing any deficiencies in the dog. The method involves acupuncture, Chinese herbs, and food energetics to reverse the condition.
5. Use food and diet as medicine and feed fresh and whole food to your dog. Packaged dog food has harmful preservatives and many of them also cause the condition.
6. Give fresh spring or filtered water to your dog.
7. Minimize electromagnetic frequencies to reduce your dog’s exposure to them. These frequencies cause a number of hormonal and thyroid-related problems in dogs.
8.Have a healthy lifestyle and give your dog plenty of exercises. Due to hypothyroid, he may not be able to workout like other dogs but start little and support your dog in building stamina.
Hypothyroidism is an irreversible condition but following a healthy lifestyle and using natural treatment options, along with conventional medication, will help in bettering the dog’s condition.
Moreover, you can also use CBD oil to treat and manage hypothyroidism in dogs. When getting one for your canine, make sure that you choose from the best CBD oil for dogs brands and options.
Diet and Nutrition - Best Dog Food for Hypothyroidism
‘What is the best diet for dogs having hypothyroidism?’
Dogs having hypothyroidism have special dietary needs and in case your dog develops the condition, you will need to give him a special kind of dog food. They cannot survive on the usual diet and will need food that is specifically formulated for them.
Here are the top choices of best dog food for a hypothyroid dog.
- Wellness CORE Grain-Free Turkey, Chicken Liver & Turkey Liver Formula
- Halo Holistic Chicken & Chicken Liver Adult Dry Dog Food
- Nutro Wholesome Essentials Large Breed Adult Farm-Raised Chicken
- Diamond Naturals Beef Meal & Rice Formula Adult Dry Dog Food
- Taste of the Wild High Prairie Grain-Free Dry Dog Food
- Blue Buffalo Wilderness Chicken Recipe Grain-Free Dry Dog Food
- Blue Buffalo Freedom Adult Chicken Recipe Grain-Free Dry Dog Food
- Merrick Grain-Free Chicken + Sweet Potato Recipe Dry Dog Food
- Forza10 Sensitive Digestion Grain-Free Dry Dog Food
- Taste Of The Wild Pacific Stream Grain-Free Dry Food
Other than these options, you can also prepare the food at home and feed him fresh food. Moreover, you can also check organic dog food options to choose from for your dog.
Prevention: How to Prevent Hypothyroidism in Dogs?
Though hypothyroidism could happen to any dog, it is a preventable condition and, usually, it is easier to prevent it than its treatment. Below are some ways to prevent hypothyroidism in dogs.
- Protect your dog’s neck and do not use hard and inflexible collars and leashes.
- Feed high-quality raw or organic food and avoid processed dog food.
- Add essential supplements to your dog’s diet. These supplements should include minerals, vitamins, Omega-3 oil, and probiotics.
- Minimize your dog’s exposure to toxins and vaccinations. Give a semi-annual detox to your dog and keep him safe and clean, inside out.
- Get your dog’s neck checked by a physiotherapist or vet to make sure that it is healthy.
- Check your dog’s glands and get them checked annually. Start the testing at the age of 5 or earlier if you see any signs of hypothyroidism.
We know that prevention is not possible every time but the least we can do is to try different methods to avoid the condition.
Hypothyroidism is a serious health condition and if left untreated, it could cause coma and death in dogs. Moreover, it could also cause aggression and seizures in dogs. Therefore, it is important to treat it in time and before it causes fatal damage to your canine.