{"url":"https://www.zooplus.co.uk/magazine/dog/dog-health-and-care/hyperthyroidism-in-dogs","title":"Hyperthyroidism in Dogs","mag_id":384359,"is_single":true,"cat_name":"Dog","sub_cat_id":143,"sub_cat_name":"Dog Health and Care","cat_id":3410}
The thyroid gland is located on either side of your dog's windpipe. Despite its small size, it plays a significant role in your dog's health. Find out how hyperthyroidism can occur in dogs and the connection it has with feeding them raw meat in this comprehensive guide.
Hyperthyroidism can be life-threatening in humans, especially during a so-called thyroid storm when there is a sudden surge in thyroid hormones, leading to a dangerous metabolic disturbance. In dogs, however, hyperthyroidism (hyperthyreosis) or a thyroid storm is extremely rare. Nevertheless, this hormonal imbalance can harm your dog, particularly if it’s due to a malignant tumour.
Symptoms: What are the typical signs of hyperthyroidism in dogs?
Hyperthyroidism in dogs can affect almost all of their organs. Consequently, a wide array of symptoms can occur:
Your dog may be restless and pant more frequently.
It might lose weight despite having a normal or increased appetite.
Its heart rate may be rapid (tachycardia).
It could have difficulties swallowing.
It might be excessively thirsty with increased urine output (polydipsia and polyuria).
It may exhibit changes in behaviour, such as sudden aggression or fear.
Its fur could appear unkempt.
It could gag or vomit frequently.
Most dog owners first notice a change in their pets’ demeanour. Some affected dogs may suddenly display aggressive behaviour. If a tumour is the cause, they may later feel a lump in the thyroid area.
Excessive thirst can also be a sign of an overactive thyroid in dogs
How Common is Hyperthyroidism in Dogs?
Thyroid gland hyperfunction is much rarer in dogs than hypofunction. This contrasts with cats, where hyperthyroidism is more common.
Diagnosis: How is hyperthyroidism in dogs confirmed?
If your dog seems different or shows certain signs of illness, you should have it checked by your vet. Following a general clinical examination, the vet may perform various tests to check the thyroid gland function.
Analysis of Blood Values
Your vet will first take blood from your four-legged friend. Special laboratory equipment can then determine important thyroid levels such as thyroxine (T4), free thyroxine (fT4), and thyroid-stimulating hormone (TSH). An elevated T4 level confirms the suspicion of hyperthyroidism in dogs. However, this parameter may still be within the normal range.
Further Tests
As a result, further examinations (e.g., ultrasound) are very helpful for your vet in identifying a causative tumour. Using scintigraphy and the application of radioisotopes, the vet can also diagnose the presence of disturbed glandular tissue.
Treatment: How is hyperthyroidism in dogs treated?
Treatment of hyperthyroidism aims to normalise hormone levels by addressing the cause of the thyroid disease. In the case of a tumour, for instance, surgery to remove hormone-producing tissue or radiation (e.g., radioiodine therapy) may be advisable. Depending on the tumour’s size, as well as the extent and stage of the cancer, chemotherapy or a combination of treatments may also be helpful.
Which Medications do Dogs with Hyperthyroidism Receive?
If complete removal of the thyroid gland in your dog is inevitable, it will require lifelong medication after surgery. Hormone replacement therapy is carried out by administering thyroxine. Your vet will individually adjust the dosage for your dog to avoid shifting from hyperfunction to a deficiency.
Diet: What to feed a dog with hyperthyroidism?
If you’re feeding your dog through the BARF method, you should ensure that throat meat contains no thyroid tissue, as this can often trigger hyperthyroidism. Therefore, it is advisable to completely avoid throat meat, especially if your dog is already suffering from hyperthyroidism.
When it comes to gullet meat, caution is advised. Any remnants of thyroid tissue might trigger an overactive thyroid condition
Causes: What triggers hyperthyroidism in dogs?
When your dog’s thyroid gland releases too many hormones, it results in hyperthyroidism. This disease can have different causes than the opposite condition of hypothyroidism.
The following three causes are known to trigger hyperthyroidism in dogs:
Dietary Hyperthyroidism
BARFing increases your dog’s risk of developing hyperthyroidism because raw throat meat is known to spike T4 levels. This is due to the frequent presence of thyroid tissue remnants from slaughtered animals.
Thyroid Tumours
Thyroid tumours, such as carcinomas, are the second possibility for the hormonal disease. They affect the function of the thyroid gland, causing it to release excess hormones.
Overdose of Medication
If your dog needs thyroid medication due to a proven hypofunction, an overdose can lead to an excess.
Prognosis: What are the chances of recovery?
The prognosis depends on the cause of the disease. Dietary hyperthyroidism can be quickly managed by changing diets. If, on the other hand, your dog is suffering from a thyroid tumour, the success of the therapy will depend on the type and aggressiveness of the tumour. If metastases are present in other organs like the lungs, this could significantly worsen the prognosis. Therefore, it’s crucial to regularly check your pet and discuss any changes with your vet at an early stage.
Prevention: How to protect your dog from hyperthyroidism
To prevent your dog from suffering from this hormonal disease, avoid feeding it throat meat when BARFing. If your dog is already affected by a thyroid condition, have its thyroid values regularly checked by your vet to prevent hormonal imbalances.
Important Note: The content provided for informational purposes only and is not intended to replace professional veterinary advice, diagnosis or treatment. If you have any questions or concerns about your pet's health, please always consult a licensed veterinarian.
Franziska G., Veterinarian
At the Justus-Liebig-University of Giessen I was extensively trained as a veterinarian and was able to gain experience in various fields such as small animal, large animal and exotic animal medicine as well as pharmacology, pathology and food hygiene.
Since then, I have been working not only as a veterinary author, but also on my scientifically driven dissertation. My goal is to better protect animals from pathogenic bacterial organisms in the future.
Besides my veterinary knowledge, I also share my own experiences as a happy dog owner and can thus understand and enlighten fears and problems as well as other important questions about animal health.
Although the heat period is an entirely natural process for female dogs, irritation at stains on the new carpet, fear of an unwanted pregnancy or their pet's strange behaviour can cause many dog owners to worry. Find out here everything you need to know about your female dog's heat period and how you can both overcome this without any stress.
16 February 2024 |Leishmaniasis is an infectious disease transmitted by sandflies and can often prove fatal for dogs. Find out how you can protect your dog and how to recognise and treat the disease should it emerge.
Neutering has traditionally been a standard veterinary practice, but is it universally recommended? What distinguishes neutering from sterilisation and what expenses should a dog owner anticipate? Here, you can discover all the essential information concerning the advantages and disadvantages of neutering your dog.
