Dog Hypothyroidism

A common disease seen in middle age to elderly dogs is hypothyroidism. The thyroid gland is a butterfly shaped gland that sits in the throat surrounding the trachea, or windpipe. It is responsible for producing hormones such as T4 or levothyroxine, T3, and TSH, which help regulate growth and metabolism. It also stores iodine in the body. 

If this gland becomes underactive, it starts to under produce hormones, and can cause signs of illness called hypothyroidism. The gland often becomes underactive due to an atrophy of the gland or due to lymphocytic thyroiditis, a condition in which immune cells such as lymphocytes infiltrate the gland and cause the gland to become replaced with fibrous tissue (scar tissue). It can also be caused by the immune system attacking the thyroid and producing autoantibodies. 

Signs that your dog may have an underactive thyroid include hair loss (alopecia) or thinning hair coat, weight gain, mental dullness, fatigue, cold intolerance, infertility, and neurological deficits. Since these symptoms can also be seen with other serious diseases, if your pet is exhibiting any of these signs please schedule an appointment with us as soon as possible. 

An examination and review of the pet’s history may reveal thinning hair, hair loss, weight gain, chronic skin conditions such as ear infections or skin infections, or other signs which may make hypothyroidism a likely culprit. Likely a blood sample will be taken to look at liver and kidney functions, red and white blood cells, and a thyroid or T4 level. Additional blood work to look at TSH, free T4, or T3 may be required to get a diagnosis.

If your pet does indeed have a lowered T4 level, a diagnosis of hypothyroidism will likely be made.  Concurrent illnesses can interfere with this testing, so additional testing may be needed, or a treatment trial may be utilized to help definitively diagnose this. The treatment of choice is an oral medication called L-thyroxine, levothyroxine, soloxine, or thyrozine. This is a lifelong treatment and is usually given once to twice a day. Follow up in the form of periodic blood work is required while your pet is on this medication. If you are concerned your pet has hypothyroidism, please schedule an appointment today!
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12624 Bass Lake Road
Maple Grove, MN 55369
Located just east of highway 494 on Bass Lake Road,
behind Culver's.

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Plymouth, Maple Grove, Brooklyn Center, Brooklyn Park, Osseo, Corcoran, Champlin, New Hope, Minnetonka, Minneapolis, Rogers, Robbinsdale and Golden Valley, Minnesota (MN).