Conveniently, the main use of iodine in the body is the production of thyroid hormone, so a deficient diet shouldnt cause any other health issues in a hyperthyroid cat. Symptoms include weight loss, muscle wasting, increased appetite, increased thirst and urination, vomiting, unkempt appearance, and sometimes hyperactivity. Pediatrics, 1998. "The most common clinical sign of hyperthyroidism is weight loss due to the increased rate of metabolism despite an increased appetite.". Certain studies suggest that in some hyperthyroid cats, limiting the amount of iodine in the diet may be a viable option for treating this disease. When x-rays, or any ionizing radiation, pass through the body they cause electrons to be ejected from atoms, leaving behind positive ions. Treatment for Hypothyroidism in Cats. Weight seemed to stabilize in the long-term setting, with minimal increases between 8 and 12 months and at 24 months after radioactive iodine treatment. A seven hour airplane trip exposes passengers to 0.02 mSv of radiation, which is a fraction of the exposure of a standard Chest x-ray (0.1 mSv). 1. Annual blood and urine tests are important in all cats seven years and older to detect hyperthyroidism before potentially irreversible damage occurs. In the US, the average person is exposed to an additional 3.0 mSv/yr from medical sources (predominantly CT scans). Milner R.J., Channell C.D., Levy J.K., et al., Survival Times for Cats with Hyperthyroidism Treated with Iodine 131, Methimazole, or Both: 167 Cases (1996-2003). This is why one of the first signs of thyroid disease may be a change in weight weight gain if the thyroid is underactive and weight loss if the thyroid is overactive. Of 135 patients with documented pubertal status . 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. Chance of significant, unhealthy weight gain is increased. During treatment, radioactive iodine is administered as an injection and is quickly absorbed into the bloodstream. These statistics are averages and do not predict what is going to happen to you. Surgical patients may become hyperthyroid again if abnormal cells are missed during surgery or if new abnormal cells develop. Standards for Protection against Radiation. What Treats Can I Give my Dog with CalciumOxalateStones? 2. Regardless of radiation exposure, the average overall lifetime risk of developing an invasive cancer is 37.5% for women and 44.9% for men. My pet has kidney disease what kind of diet should I feed. Secondary Problems In an effort to put some weight back on him we are still feeding him turkey and gravy baby food in the morning to supplement the dry food. If this is the case with your cat, paying special attention to specific nutrients such as dietary phosphorus (a key player in chronic kidney disease) may be required. For the first two weeks after I-131: Keep your cat indoors or supervised when outside to prevent contact with other people. That was part of the problem we had before treatment. Blog written by Dr. Daisy Spears in conjunction with Dr. Linder. 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. Not all veterinary facilities perform the procedure. So in this case the targeted radiation exposure is actually increasing survival for these patients. Cats also sweat through their paws and the sweat will have trace amounts of radioactive iodine. Iodine-131, Hyperthyroidism, and Radioactive Iodine Therapy Iodine-131 (I-131) is a radioisotope of iodine with a physical half-life of 8.02 days; its primary decay emissions include a 606 keV - particle with 89.6% abundance and a 364 keV -ray with 81.5% abundance (Knolls Atomic Power Lab 2010). And not only do we love the pets, we also love their people, and you are our reason for making this site. 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). A Multicompartmental Model for Iodide, Thyroxine, and Triiodothyronine Metabolism in Normal and Spontaneously Hyperthyroid Cats. Radioactive-iodine therapy is becoming increasingly popular when dealing with hyperthyroidism in cats. How does airline travel expose me to radiation? The slow onset of signs means that cat owners will often miss these changes until the late stages of disease. Hence people who's hyperthyroid cats are treated with radioiodine would be expected to have a potentially increased risk of developing cancer over the remainder of their lifetime as the result of that exposure of no more than 1/100th of 1 percent. After initial stabilisation with oral medications, a number of curative treatments are also available. Lifelong administration of methimazole can control the effects of an overactive thyroid gland. Weight change was analyzed in only 228 patients and 84% gained weight by 1 year after radioactive iodine therapy. Currently, there's only one FDA approved medication to treat feline hyperthyroidism called methimazole. The brand name of methimazole is called Felimazole. The dosage may vary but typically a cat is given this oral medication twice a day, every 12 hours. . GFR results are used to determine the functional status of the kidneys, and identify cats with subclinical renal disease. One to two weeks after surgery, another TT4 level is measured. . If your cat is showing signs of illness or depression, please contact PVESC. Even after treatment it may take a long time to reverse weight loss and muscle loss that occurred before your cat's diagnosis. The American Thyroid Association notes that weight gain develops over a long time and may have many causes other than the underactive thyroid. Hyperthyroidism is a common disease in cats, and mostly afflicts cats middle-aged and older. A small number of cats will remain hyperthyroid after treatment, if this is the case your cat will need . Luckily these risks will diminish in time following successful radioiodine therapy and a return to a persistently normal thyroid level. (8,9) Replacement hormone products currently on the market, both synthetic and glandular, are not comparable to our own hormone, and in some people, never feel "right". There are currently no known preventive measures for hyperthyroidism, but early diagnosis decreases the secondary problems and improves the prognosis. Usually, the TT4 level is so high that there is no question about the diagnosis (see the handout "Thyroid Hormone Testing in Cats"). Anti-thyroid drugs act by reducing the production and release of thyroid hormone from the thyroid gland. With this therapy, you take radioactive iodine (radioiodine) by mouth. Before treatment he was ravenous and losing weight -- typical of cats with that disorder I'm told. Thyroid hormones affect nearly all of the organs in the body; therefore, thyroid disease often causes secondary problems. It does, however, involve the handling and injection of a radioactive substance that is only permitted at facilities specially licensed to use radioisotopes. Amazingly despite over 35 years of veterinary experience treating hyperthyroid cats with radioiodine there are virtually no reported side effects. In a cat treated with radioactive iodine, the drool will contain radioactive materials. Also, I wonder if there is home-testing equipment to track the household dispersal of the radioactive contaminants that he emits after his treatment and something else to monitor and determine my exposure to the 131I remnants. Domestic airline pilots are exposed to an additional 2.2 mSv per year, about the same dose as a brain CT. As you can see from the table below, the estimated risk of developing cancer from exposure to 0.1 Gy (= 100mSv), while it varies with the age of the individual, is something less than 1% for adults. Most cats with uncomplicated hyperthyroidism will live several years following treatment of hyperthyroidism, unless they develop another disease. Some people also feel flushed. The radioiodine is eliminated in urine and feces. 197(2): p. 125-136. Diagnosis Your veterinarian has recommended I131 for your cat. However once the diagnosis of hyperthyroidism has been made, and no other illnesses are identified, the motivation to perform further diagnostics, especially those that require the need for anesthetics or are invasive may be lost. Vet Rad & Ultrasound, 1994. It is given one to three times daily and must be continued for the remainder of the pet's life. The current Nuclear Regulatory Commission radiation dose limits for individual members of the public are listed below. Risks from other illness. Endocrinology, 1988. Learn more about the Clinical Nutrition Team at Tufts. Subscribe to always know when we add new material! Aim: Analysis and follow up of body weight after radioiodine therapy (RITh) of hyperthyroidism, since excessive weight gain is a common complaint among these patients. Home & Forums | Radioactive iodine (I-131) is a very safe and effective treatment for hyperthyroidism. The recommended food for cats with thyroid problems is high in protein yet low in carbohydrates, iodine (around 0.32 ppm) and phosphate. Before deciding the form of treatment, several tests are performed, including additional blood tests, a urinalysis, chest radiographs (X-rays), an ECG, and blood pressure measurements. 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? Now the question is what risk does one obtain from receiving an exposure of 1 mSv? Thyrotoxic cardiomyopathy may develop because the heart enlarges and thickens to meet the increased metabolic demands. Slater M.R., Komkov A., Robinson L.E., et al., Long-Term Follow-up of Hyperthyroid Cats Treated with Iodine-131. Hyperthyroid cats suffer overactive thyroid glands, circulating too much thyroid hormone through their system and affecting nearly every organ. Although it has a slightly higher iodine content than the previous option, Tiki Cat Hanalei Luau Wild Salmon is the best value for money. The study followed people for 26 years after two or more treatments. Surgical removal of the gland under general anesthetic was another option. The Disadvantages of Radioiodine Therapy Treatment for Cats, American Veterinary Medical Imaging: Feline Hyperthyroidism, Washington State University College of Veterinary Medicine: Radioactive Iodine Treatment of Hyperthyroid Cats, Washington State University College of Veterinary Medicine: Hyperthyroidism in the Cat, Cornell University College of Veterinary Medicine: Hyperthyroidism in Cats. You should use the following methods for disposing of your cat's waste that may contain trace amounts of radiation. 1 Radioactive iodine (RAI)] is generally considered the optimal treatment for hyperthyroidism in cats. Often, treating hyperthyroidism will unmask hidden kidney failure that will require additional care and is best detected early in the course of the disease. This test can also help the doctor determine the cause of your hyperthyroidism and get other information about your thyroid tissue. It is best to perform a nuclear scan before surgery to rule out ectopic thyroid tissue. J Vet Intern Med, 2001. When this occurs, a second test, usually afree T4 by equilibrium dialysis (FT4 by ED)or aT3 suppression test,is performed.
They were randomized into 2 groups for continuous antithyroid and radioiodine treatment. . Learn more about radioiodine therapy for hyperthyroidism, Learn about radioiodine therapy for thyroid carcinoma, Learn more aboutSamariumtherapy for primary or metastatic bone tumors. Because of strict treatment guidelines, most facilities will not allow visitors during this quarantine period. These positive ions, or free radicals, can cause damage to DNA. 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. Only certain facilities perform this procedure, which consists of giving your cat a shot of radioactive iodine, which gets rid of abnormal thyroid cells without harming normal ones. Since platelets are essential for blood clotting, thrombocytopenia may lead to problems with excessive bleeding. A standard Chest x-ray is 0.1 mSv. This can be accomplished in several ways: Radioactive iodine therapy. Elevated thyroid hormones stimulate an increased heart rate and a stronger contraction of the heart muscle, and can cause thickening of the left ventricle of the heart over time. You'll have to give him this drug twice daily for the rest of his life, which treats but doesn't cure the condition. NRC Regulations Unfortunately, 131I has a rather high-energy gamma emission that is difficult to shield. Signs of anxiety in a cat including pacing, yowling for no apparent reason, and restlessness are a common symptom of feline hyperthyroidism. Lack of appetite. When it comes to survival, the studies that have been done show that cats cured of their thyroid disease by radioactive iodine live much longer (up to twice as long) when compared to hyperthyroid cats treated by methimazole. A prescription diet is available that lowers thyroid hormone, but for it to work your cat can't ever eat any other food. Most cats with hyperthyroidism have elevated levels of the thyroid hormone T4 in their bloodstream, but a small percentage of cats with hyperthyroidism have T4 levels within the normal range. RAI is a form of radioactive nuclear medication that permanently destroys thyroid tissue. At 1 and 3 months after the treatment, a blood test for thyroid and kidney function should be done by your veterinarian. In almost all cases, your thyroid hormone levels will return to normal or below normal after radioactive iodine treatment. She has a Bachelor of Arts in English from New York University and an Associate of Arts from the American Academy of Dramatics Arts, New York City. The chronic elevation of circulating thyroid hormone levels in cats with hyperthyroidism leads to changes in their heart muscle that predispose them to developing heart failure. One major risk associated with surgical thyroidectomy is inadvertent damage to the parathyroid glands, which lie close to or within the thyroid gland and are crucial in maintaining stable blood calcium levels.