The radioactivity carries no significant risk for the cat, but precautionary protective measures are required for people who come into close contact with the cat. Rarely, a permanent reduction in thyroid-hormone levels called hypothyroidism occurs after radioactive iodine treatment. You may feel a lump on your cat's throat under his jaw. Since platelets are essential for blood clotting, thrombocytopenia may lead to problems with excessive bleeding. Dr. Deborah Linder, a board-certified veterinary nutritionist, is the head of the Tufts Obesity Clinic for Animals and has had articles appear in Eating Well, the Boston Globe, AARP, SHAPE, and XM Sirius Radio Doctor Channel. The radioiodine is eliminated in urine and feces. A swollen or tender neck and feeling flushed. Surgery will be performed if your cat successfully undergoes the initial treatment without complication. Surgical removal of the affected thyroid gland(s) may be very effective. Affected cats are often restless and may become cranky or aggressive. If these tests are not diagnostic, athyroid scan (thyroid scintigraphy)can be performed at a veterinary referral center, or the TT4 can be measured again in a few weeks. Title 10, Code of Federal Regulations Risks unrelated to radioiodine therapy: For the same reasons as surgical treatment, your cat will likely be started on methimazole for about a month before radioactive iodine therapy. This can best be done by monitoring your cat's body condition, muscle condition, and weight. To scientifically prove a connection would require nearly one million patients followed closely over decades to detect the small increased risk with any confidence. Radioactive iodine therapy is curative within three months of therapy in approximately 95 percent of all hyperthyroid cases. The typical cat with hyperthyroidism is middle-aged or older; the average age of affected cats is approximately 12 years. Hyperthyroidism is too much thyroid hormone that causes weight loss so kitty should gain some weight back to a normal amount after treatment. Always check with your veterinarian before changing your pets diet, medication, or physical activity routines. In cats > 95% of the radioiodine is excreted in the urine. Pediatrics, 1998. Radioactive iodine may also affect a woman's ovaries, and some women may have irregular periods for up to a year after treatment. Recurrence of hyperthyroidism is rare after I-131 therapy. There are four treatment options for feline hyperthyroidism: medication, radioactive iodine therapy, surgery, and dietary therapy. and Turrel J.M., A Multicompartmental Model for Iodide, Thyroxine, and Triiodothyronine Metabolism in Normal and Spontaneously Hyperthyroid Cats. If the total GFR is below this number, medical therapy for hyperthyroidism may be recommended, although I-131 treatment may still be an option in specific patients. The "radiation badge" worn by x-ray techs for example is good for measuring external exposure to radiation but does nothing to measure intakes of radioactive materials which is the primary concern in the case of a cat treated with radioactive 131I. Cats with hyperthyroidism exhibit symptoms that are similar to those of humans with the disease: weight loss, increased appetite, excessive . Design and methods: Five hundred and four patients over 40 years of age with diffuse toxic goiter were treated with MMI for 18 months. Supporting Cat Health with Information and Health Studies. How long can a cat live after radioactive iodine treatment? Additionally, diet may play a significant role in managing the disease, whether as a sole treatment or as an adjunct tool to address changes in your cats body related to hyperthyroidism. TheCatSite.com is a community of cat lovers dedicated to quality cat care and cat welfare. The total effective dose equivalent to individual members of the public from the licensed operation does not exceed 1 mSv in a year, exclusive of the dose contributions from background radiation, from any administration the individual has received, from exposure to individuals administered radioactive material. Consider Hyperthyroid Treatment . If DNA is damaged, there are three possible outcomes: Diagnosis of feline hyperthyroidism is generally straightforward. However, once the underlying hyperthyroidism has been controlled, the cardiac changes will often improve or may even resolve completely. It is actually the best approach to take to minimize exposures to you and your family while allowing the cat to have post-treatment recovery time at home and not in a veterinary hospital. Ideally, the total GFR should be above 2.25 mL/min/kg. Overall, weight gain was associated with development of hypothyroidism despite levothyroxine replacement . The radioactive iodine is administered as a single injection . So in this case the targeted radiation exposure is actually increasing survival for these patients. Side effects may include fluid retention, weight gain, elevated . Since you'll have to leave your cat at the facility for several days or more, it's not a question of dropping him off at a distant veterinary hospital and then picking him up the next day. 6. However, there are a number of reasons for the precautions that your veterinarian has provided you that I will discuss below. Hence additional separation between the patient and children are unnecessary. When this occurs, a second test, usually afree T4 by equilibrium dialysis (FT4 by ED)or aT3 suppression test,is performed. Methimazole is also given before surgery to determine if the cat has a secondary medical condition, such as kidney or liver disease masked by hyperthyroidism. Should we just cut him off "cold turkey" (pun intended) and hope he finds fulfillment and eventual weight gain with his old diet of dry food? In some cases, complications involving other organs may worsen this prognosis. Set up your myVCA account today. The dose of radiation used during radioactive iodine treatment is very low, but there are some precautions you'll need to take after treatment: avoid prolonged close contact with children and pregnant women for a few days or weeks women should avoid getting pregnant for at least 6 months men should not father a child for at least 4 months The remainder is gone in about the next two months or so. What are the risks of my cat becoming hypothyroid? The thyroid takes up the radioactive iodine, which destroys cells in the thyroid. Both cardiomyopathy and hypertension are potentially reversible with appropriate treatment of the disease. Cats may also continue to show signs of hyperthyroidism, including vomiting and diarrhea, for 3-4 weeks after the radioiodine therapy as the disease continues to resolve. Prominent in the regulations established by the Nuclear Regulatory Commission for radioactive materials users are guidelines that limit exposure to radiation workers, and members of the general public. Do not allow your cat to sleep against your body. If we restrict iodine, production of thyroxine decreases. Objective: To investigate the long-term effects of continuous methimazole (MMI) therapy. Radioiodine treatment avoids surgery, anesthesia, and anti-thyroid drugs. Is radioactive iodine treatment safe? It requires two round-trips for you. Methimazole blocks excess thyroid hormone production rather than destroying the abnormal thyroid tissue, so the medication must be given for the rest of the cat's life. They may develop periodic vomiting or diarrhea, and fur may appear unkempt. Part 20, Standards for protection against radiation Ultimately of course, these conditions can be diagnosed. Some cats may experience side effects from medication, however, including vomiting, anorexia, fever, anemia, and lethargy. The cell dies (only occurs with very high doses). It is important to remember that old age is not a disease. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society. This lowers the amount of radiation exposure to your bladder. The dose of radioactive iodine is taken orally. If your cat requires daily medications for issues other than hyperthyroidism, he's not a candidate for radioactive iodine therapy. Removal of the thyroid glands, called surgical thyroidectomy, is a relatively straightforward surgical procedure that has a good success rate. What is not taken up by the thyroid will be present in the cat's bodily fluids and will primarily be voided in the cat's urine (in those first four days at the vet hospital). Treatment usually requires one or two weeks of hospitalization at a veterinary hospital licensed to administer radiation therapy. I am certain that your veterinarian probably told you to take care when handling the litter and to wash your hands thoroughly after handling litter, the cat, and items that the cat came into contact with. What happens after my cat is released from the hospital? TheCatSite.com participates in select affiliate advertising programs, including the Amazon Services LLC Associates Program. under the skin, like a vaccine) and the radioactive iodine is quickly absorbed into the bloodstream. It is also common for hyperthyroid cats to exhibit increased vocalizing, particularly at night. You may gain weight after you undergo radioactive iodine treatment. GFR results are used to determine the functional status of the kidneys, and identify cats with subclinical renal disease. In almost all cases, your thyroid hormone levels will return to normal or below normal after radioactive iodine treatment. This isnotan iodine-free diet but a diet with a controlled iodine content of 0.2ppma minimal amount. The risks associated with low level ingestion of radioactive iodine relate to an increased risk of developing thyroid cancer. Gained over three pounds! Does radioactive iodine treatment cause weight gain? Jane Meggitt has been a writer for more than 20 years. There are several hypothesized causes of hyperthyroidism. There are three common forms of treatment for hyperthyroidism in cats: medication, radioactive iodine therapy and surgery. For this reason, some cats with hyperthyroidism may require additional treatment to control secondary heart disease. American Academy of Pediatrics. Researchers estimated a 12% increased risk for death from breast cancer and a 5% increased risk for death from . When available, radioactive iodine therapy is the treatment of choice for cats with hyperthyroidism. A special diet for cats with hyperthyroidism. The risk to these cats is the simple fact that many cats in the age range when cats develop hyperthyroidism (8+ years) also develop other diseases. For some cats, a veterinary therapeutic diet low in iodine may be all thats required to control symptoms. radioactive iodine All three treatments will reduce thyroid hormone levels and the signs of hyperthyroidism. This treatment is appropriate for cats with more surgical risk due to other health problems or who are exceptionally old. 4. However, an overactive thyroid is quite common. AAFCO Doesnt Approve Pet Foods, A broken heart: Risk of heart disease in boutique or grain-free diets and exotic ingredients, Its Not Just Grain-Free: An Update on Diet-Associated Dilated Cardiomyopathy. In cats, an underactive thyroid is extremely rare. The thyroid cells are damaged or destroyed, but that's the whole idea other cells are left untouched. So excited we decided to go this route and cure her instead of just treating with daily medication. A veterinarian who suspects a cat has a thyroid problem will conduct a physical examination and palpate the cats neck area to check for an enlarged thyroid gland (see Figure 2). (At my facility we treat people but many of the concepts are the same, it is just that patient compliance is easier to obtain with people.) Hypertension develops due to the increased pumping pressure and elevated heart rate that occurs with hyperthyroidism. I have a cat also and I know when she is happy and purring while sitting on my lap getting strokes, she drools. Over ten years of clinical nutrition research revealed that by controlling dietary levels of iodine, the hyperthyroid cat's body would resume normal thyroid hormone production. Although the cause of feline hyperthyroidism is not known, possible contributing factors include deficiencies or excesses of certain compounds in the diet and chronic exposure to thyroid-disrupting chemicals in food or the environment.