Hypothyroidism is a deficiency of thyroid hormone. This deficiency is produced by immune-mediated destruction of the thyroid gland or by natural atrophy (wasting away) of the gland. Hypothyroidism generally develops in middle-aged or elderly dogs. With this condition, you will often see hair loss, abnormal skin conditions with or without skin infections, obesity and lethargy (a very lazy/sleepy dog). The thyroid hormone serves as a sort of volume dial for metabolism. Every system in the body can be affected by low levels of thyroid hormone which is why it leads to symptoms occurring in multiple body systems.
If your pet is diagnosed with hypothyroidism, he/she will be started on a medication that is given twice daily, and your pet will remain on this medication for life. Whenever an animal goes on long term medication, periodic blood testing is required. It is important to know if the medication dose is too low which would leave your pet inadequately treated. Or too high which would lead to excessive water consumption, restlessness and weight loss.
After your dog has started the medication, we will need you to bring him/her in for a weigh-in and a T4 blood test. This blood sample will need to be taken 4 to 6 hours after their morning pill. Six months from starting the medication we will need to book an appointment with your pet’s veterinarian for a full physical exam, current weight and another T4 blood test. The physical exam is needed to ensure that all the physical signs of the condition are under control. Tracking your pet’s body weight is a powerful monitoring tool for hypothyroidism.
An annual exam and T4 is all that is required from this point on as long as no other conditions or concerns arise with your pet. We will try to coordinate this with your pet’s annual vaccination appointment.
Once diagnosed and stabilized, a dog with hypothyroidism is relatively simple to manage. We all want what is best for your pet!
Written by: Darlene Cannon, RVT