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Feline Radioiodine I-131 Therapy

Treatment for Feline Hyperthyroidism

What is Hyperthyroidism?

Hyperthyroidism is an overactive thyroid gland, which is common in older cats.  Cats that have been classified as hyperthyroid can have the following signs and symptoms:

· Rough or greasy hair coat

· Losing weight but eating normally

· Behavior changes

· Rapid heart rate and blood pressure

· Heart murmur and heart enlargement

· Increased liver enzymes

· Increased drinking and urination

· Vomiting

· Diarrhea

· Lethargy

Green Eyed Cat

What are the Treatment Options?

Hyperthyroidism therapy can include medications to block the manufacture of thyroid hormones, surgery, or radioactive iodine therapy.  Surgery can be difficult to perform on the small thyroid glands but in certain cases is available.   Medications can be effective in the treatment of hyperthyroidism but may require giving 1-3 tablets a day to your cat.  Other application methods of medicating are available but still require time to give to your cat. The most effective treatment for hyperthyroidism is radioactive Iodine I-131.  I-131 is a single treatment (in capsule form) and has a success rate of 95-98%. 

What is I-131?

I-131 is Radioactive iodine. It is an isotope that destroys abnormal hyperplastic tissue of the thyroid and normalizes thyroid levels.

Kitten Sleeping in Pet Bed
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