Although the thyroid gland enlarges in hyperthyroidism, it is usually a benign or non-malignant change. Radioactive-iodine therapy is becoming increasingly popular when dealing with hyperthyroidism in cats. 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. ), family history (genetics) or radiation exposure. By 14 days after treatment, the radioactivity will have decayed to a very low level. Hyperthyroid cats suffer overactive thyroid glands, circulating too much thyroid hormone through their system and affecting nearly every organ. 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.
Older cats are at greater risk for developing hyperthyroidism. The prognosis for cats with hyperthyroidism is generally good with appropriate therapy. Dr. Freeman has received research or residency funding from, given sponsored lectures for, or provided professional services for Aratana Therapeutics, Elanco, Guiding Stars Licencing Co LLC, Hills Pet Nutrition, Nestl Purina PetCare, P&G Petcare (now Mars), and Royal Canin. For this reason, some cats with hyperthyroidism may require additional treatment to control secondary heart disease. Your doctor will order a test called a radioactive iodine uptake and scan to determine the dose you will need. Jane Meggitt has been a writer for more than 20 years. These complications include cerebrovascular events (i.e., strokes) and the premature exacerbation of pre-existing kidney disease. The medication can be given life-long or to stabilize the cat before other treatment. The treatment lowers or eliminates hormone production and may decrease the size of the goiter. These include an iodine-restricted diet, medications, and radioactive iodine therapy. While I do not know the amount of radioactive 131I that was administered to your cat, the recommendations that your veterinarian has given you are very standard for the industry. In some cases, the cat will develop a heart murmur associated with cardiomyopathy. The following question was answered by an expert in the appropriate field: What testing equipment and protective clothing do you recommend for a nontechnical person who will be giving home care to an 18-year-old blind cat after he has spent four days recovering in the animal hospital from 131I treatment? Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society. Occasionally cats will act like they may have a sore throat for a couple of days after the radioiodine therapy. Since hyperthyroidism can predispose a cat to other conditions, it is important to evaluate general health, with particular focus on the heart and kidneys. 2000-2023 TheCatSite.com. Affected cats are often restless and may become cranky or aggressive. Clients frequently have the following 2 questions when considering radioiodine therapy for their cat's hyperthyroidism. There are three common forms of treatment for hyperthyroidism in cats: medication, radioactive iodine therapy and surgery. Of 135 patients with documented pubertal status . Radioactive iodine therapy is curative within three months of therapy in approximately 95 percent of all hyperthyroid cases. What are the risks of my cat becoming hypothyroid? I-131 therapy does not require anesthesia and eliminates the need for daily medication. Affiliate of Mars Inc. 2023 | Copyright VCA Animal Hospitals all rights reserved. Always check with your veterinarian before changing your pets diet, medication, or physical activity routines. Having said that, the clients who own the cats we treat with radioiodine should make every effort to avoid ingesting any contents from the litter box. Cats receive a single dose of radioactive iodine by either subcutaneous injection or by a capsule given by mouth. All middle-aged and senior cats should receive a complete physical examination by a veterinarian every six months. Hyperthyroidism & Liver Function in Cats, Intervals of Depo-Medrol Injections for Cats. Pediatrics, 1998. Because the radioactive iodine used (known as iodine 131) may expose those around you to the effects of radiation (and theoretically negatively affect their thyroid glands), you will be given guidelines on how to prevent such exposure. Signs of anxiety in a cat including pacing, yowling for no apparent reason, and restlessness are a common symptom of feline hyperthyroidism. Radioactive iodine therapy is a very effective way to treat hyperthyroidism (I-131).
However, these options tend to be expensive and not possible for all pet owners. While the treatment is fairly expensive, over the long term it could be cheaper than medication and is on a par with surgical treatment. In some cases, complications involving other organs may worsen this prognosis. If thyroid disease is a possibility, your veterinarian will likely order a blood chemistry panel and an analysis of thyroid hormone levels. Weight change was analyzed in only 228 patients and 84% gained weight by 1 year after radioactive iodine therapy. Our cat was treated for hyperthyroidism and has been back home for about two weeks. 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). The only method to estimate that dose is to measure the radioiodine within your own thyroid and the types of equipment to measure that uptake are very expensive and difficult to interpret. Lifelong administration of methimazole can control the effects of an overactive thyroid gland. Cats treated with radioactive iodine for their hyperthyroidism have several risks unrelated to the radioiodine therapy itself. Why? This can best be done by monitoring your cats body condition, muscle condition, and weight. The iodine, which is required for the production of both T3 and T4, is taken up by the thyroid gland and the emitted radiation destroys the abnormal thyroid tissue without damaging the surrounding tissues or the parathyroid glands. Medication Malcolm Weir, DVM, MSc, MPH; Krista Williams, BSc, DVM; Robin Downing, DVM, CVPP, CCRP, DAAPM; Ernest Ward, DVM. Once his radiation levels come down and you can bring him home, you still have to keep him away from young children and pregnant women, as he'll pass small amounts of radioactive iodine through his urine for approximately two weeks. Why isn't there a study directly linking medical imaging and cancer? Fewer than 2% of hyperthyroid cases in cats involve malignant thyroid gland tumors. Risks unrelated to radioiodine therapy: Cats treated with radioactive iodine for their hyperthyroidism have several risks unrelated to the radioiodine therapy itself. The anti-thyroid pill is methimazole, also known as Tapazole. Many doctors recommend that women avoid becoming pregnant for 6 months to a year after treatment. Endocrinology, 1988. Unfortunately, 131I has a rather high-energy gamma emission that is difficult to shield. One way to treat a cat with hyperthyroidism is with an oral medication that contains methimazole. 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. Clinical signs include lethargy, dullness, obesity, oily skin, and matted fur. Want to read more information on feeding your pet? The treatment options for hyperthyroidism are: Oral medication. 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. If DNA is damaged, there are three possible outcomes: Affected cats produce too much thyroid hormone. The advantage of surgery is that it is likely to produce a long-term or permanent cure in most cats, and therefore eliminates the need for long-term medication. I'll be honest, the last thing I (or my vet) worried about with Sara was gaining weight. Luckily these risks will diminish in time following successful radioiodine therapy and a return to a persistently normal thyroid level. Radioactive iodine. (For example, for human patients we provide instructions such as "sleep in separate beds" and "stay at least 1 meter away from others as much as possible.") 4. No ill effects have been noted in the children born to parents who received radioactive iodine in the past. What are other nutritional concerns for my hyperthyroid cat? You should use the following methods for disposing of your cat's waste that may contain trace amounts of radiation. Now that I know my cat has hyperthyroidism, what do I do? Because the risk from exposure to radiation in children is generally considered greater than the risk from the same exposure in adults[7], radiation precautions for children and pregnant women are more restrictive than for adults.The release instructions advising clients of hyperthyroid cats being discharged following radioiodine therapy at AVMI advise that pregnant women and children (defined as individuals less than 18 years of age) avoid contact (defined as a proximity of less than 6 feet) with the patient for a period of 12 days following discharge. By
Vet Rad & Ultrasound, 1994. Often, treating hyperthyroidism will unmask hidden kidney failure that will require additional care and is best detected early in the course of the disease. She's lost a pound in less than two weeks, so yeah, I'm glad I let her eat as much as she wanted. I-131 is normally a health concern after the .
. NRC Regulations Even after treatment it may take a long time to reverse weight loss and muscle loss that occurred before your cat's diagnosis. . Note that the reference above excluding licensee's from considering "exposure to individuals administered radioactive material" in their compliance with the NRC regulartions does not apply to animals. Cats managed with diet or medication generally do well as long as their feeding is consistent, their medication is administered routinely, and follow-up blood and diagnostic tests are performed as scheduled. Protein and Carbohydrate Sources of Home-cooked Pet Diets, Deborah E. Linder, DVM, MS, DACVIM (Nutrition), Diet-associated dilated cardiomyopathy: The cause is not yet known but it hasnt gone away, Too hot? 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. When available, radioactive iodine therapy is the treatment of choice for cats with hyperthyroidism. An anti-thyroid medication, like methimazole. Radioactive iodine therapy. Many older cats with overactive thyroids have actual enlargement of the gland which can be felt in the neck by your veterinarian. If your cat is showing signs of illness or depression, please contact PVESC. In most cases, only enough radioiodine is given to destroy that part of the gland that is functioning . 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. Usually, the TT4 level is so high that there is no question about the diagnosis (see the handout "Thyroid Hormone Testing in Cats"). In more serious cases, surgical removal of the thyroid glands may be required. Further, the litter will be radioactive as most of the radioactive iodine will be excreted via this route. Because metabolism is altered in hyperthyroidism, its important to monitor your cats weight and muscle mass. This test can also help the doctor determine the cause of your hyperthyroidism and get other information about your thyroid tissue. However, since wild-caught flaked Alaskan salmon is the first ingredient, it provides a lot of moisture. They were randomized into 2 groups for continuous antithyroid and radioiodine treatment. Cats are homed in our spacious, purpose-built radioactive iodine unit and cared for by our dedicated team of radioiodine nurses. American Academy of Pediatrics. The radioiodine (I-131) used to treat thyroid disease in people and animals emits both gamma rays and beta particles. . There are several hypothesized causes of hyperthyroidism. What about radioactive iodine treatment for children and teenagers? The cell dies (only occurs with very high doses). Both cardiomyopathy and hypertension are potentially reversible with appropriate treatment of the disease. However, because your cat will be radioactive for several days after receiving the shot, precautions must be taken during and after the treatment. And I'm so glad she did, since her kidney disease (that unmasked after methimazole treatment) went from Stage 1 chronic to Stage 4 acute on chronic last weekend. Radioactive iodine targets the thyroid tissue - as this is the only tissue in the body that uses significant quantities of iodine. How does airline travel expose me to radiation? Ultimately of course, these conditions can be diagnosed. Treatment usually requires one or two weeks of hospitalization at a veterinary hospital licensed to administer radiation therapy. Site Help | The principle advantage of Radioactive Iodine treatment for hyperthyroidism is that it tends to have a much higher success rate than medications. Although many cats diagnosed with hyperthyroid disease already have kidney disease, untreated hyperthyroidism can also cause kidney disease due to the damaging effects of hypertension on the kidneys. Did You Know? Hyperthyroidism is too much thyroid hormone that causes weight loss so kitty should gain some weight back to a normal amount after treatment. Radioiodine treatment avoids surgery, anesthesia, and anti-thyroid drugs. What they are trying to prevent is the intake (ingestion, etc.) To date the studies following hyperthyroid cats treated with radioiodine have not shown any increased incidence of cancer (thyroid or other types) associated with radioiodine therapy. For comparison, the dose for a standard Chest CT is 7 mSv. Wet food is much better for him anyhow, so this is a good time to get him settled on it. These include weight loss, increased activity, and kitten like behaviour. People may take RAI . Of course some cats treated with radioiodine for their hyperthyroidism will go on to get cancer, but in the same proportion as hyperthyroid cats treated with methimazole or surgery. Whats the difference between type 1 and 2 diabetes NHS. This helps us offset the costs of running this site, so thank you for your support! Many owners of cats with hyperthyroidism are hesitant to have radiation therapy or surgery because of their cat's advanced age. Once the correct dose of radioiodine has been determined and administered, most of the time the tumors responsible for causing the elevated thyroid levels resolve and the cats are cured. Because each cat is different, your veterinarian will advise you on the best treatment for your cat. 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. Radioactive iodine is an effective and safe treatment option for children and teenagers with an overactive thyroid gland, but will usually be given as a second-line treatment after a reasonably long course of antithyroid medication. Radioactive iodine therapy offers a cure through a simple injection that returns thyroid function to normal levels. The majority of cats treated with radioactive iodine have normal hormone levels within one to two weeks of treatment. Side effects may include fluid retention, weight gain, elevated . Thank you! Employees of facilities that utilize radioactive materials may be categorized as "radiation workers" depending on their role. In a study of 524 hyperthyroid cats treated with I-131, only 11/524 (2.1%) developed The advantages of radioactive iodine therapy are that the procedure most often cures hyperthyroidism, has no serious side effects, and does not require anesthesia. 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. Secondary Problems 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. . Calabrese E.J., Hormesis: From Marginalization to Mainstream: A Case for Hormesis as the Default Dose-Response Model in Risk Assessment. TheCatSite.com is a community of cat lovers dedicated to quality cat care and cat welfare. Radioactive iodine therapy. Natural background radiation exposure accounts for an average of 3.1 mSv/yr with variations depending on where you live. As in the case of heart disease, after the hyperthyroidism has been successfully treated, high blood pressure will often resolve, and permanent treatment for it may not be required. 6. However, unless the retinal detachment is treated immediately, permanent blindness can occur. Cats also sweat through their paws and the sweat will have trace amounts of radioactive iodine. Exposure to high levels of dietary iodine may cause susceptible cats to develop hyperthyroidism. It is acceptable to feed your feline products containing at least 30% protein and less than 15% carbohydrates. While in radiology we use radiation shielding garments (lead aprons) to reduce gamma and x-ray exposure, the energy of the 131I gamma is four to five times higher and those garments are ineffective as a shield. The overwhelming majority of cats (>95%) are cured by a single therapy with only a small percentage of cats requiring additional radioiodine therapy (4%) or becoming persistently hypothyroid (1%). These medications do not provide a cure for the disease, but they do allow either short-term or long-term control of hyperthyroidism. Only about 5% of hyperthyroid cats are younger than 10. 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. The ALARA recommendation follows the classic "less is more" argument and hence adherence to this philosophy suggests that exposures to ionizing radiation should be minimized whenever possible. Other than unexplained weight loss, your cat may also become more restless, hyperactive, vocal, and extremely hungry! Hyperthyroidism is a common condition in older cats. Does radioactive iodine treatment cause weight gain? radioactive iodine All three treatments will reduce thyroid hormone levels and the signs of hyperthyroidism. But this generally resolves without intervention. With this therapy, you take radioactive iodine (radioiodine) by mouth. In addition to reporting for a major newspaper chain, she has been published in "Horse News," "Suburban Classic," "Hoof Beats," "Equine Journal" and other publications. 1 Radioactive iodine (RAI)] is generally considered the optimal treatment for hyperthyroidism in cats. How can the age of a material be determined from the decay of a radioactive element quizlet? 4. The beta particles, which are much more potent forms of radiation, travel an average distance of less than 1 mm. We fed him some Fancy Feast again last night and he ate it all without vomiting. Hays M.T., Broome M.R. Home & Forums | The recommended food for cats with thyroid problems is high in protein yet low in carbohydrates, iodine (around 0.32 ppm) and phosphate. 228(4): p. 559-63.
You may gain weight after you undergo radioactive iodine treatment. Other therapeutic monitoring. If your cat requires daily medications for issues other than hyperthyroidism, he's not a candidate for radioactive iodine therapy. Prognosis The iodine is taken into the thyroid gland and incorporated into thyroxine. Radioactive iodine is a treatment for an overactive thyroid gland. No individual breed is known to have a greater risk, although Siamese, Burmese, Persian, Abyssinian, Tonkinese, and British shorthair breeds appear to have a somewhat decreased incidence of hyperthyroidism compared to other breeds. Most of the extra radioactive iodine is eliminated in your urine. Your veterinarian's instructions regarding separation for the two weeks are simply doing the same thing we do with people. It is used less commonly in younger children. To the best of our knowledge, answers are correct at the time they are posted. This treatment involves administering an injection of iodine with a radioactive substance attached. If radioactive iodine therapy won't work for you and your cat, alternatives are available. This I131 injection accumulates in the abnormal thyroid tissue, and the radioactivity kills the abnormal tissue without harming other vital structures nearby. Blog written by Dr. Daisy Spears in conjunction with Dr. Linder. Some rare cases of hyperthyroid disease are caused by malignant tumors known as thyroid adenocarcinomas. They may have increased water consumption and urination. This may take 8 to 12 weeks or longer. In cases where radioactive iodine therapy is not successful, the treatment can be repeated. Some people also feel flushed. These positive ions, or free radicals, can cause damage to DNA. In some cases, a decrease in blood platelets (thrombocytopenia) may also occur. He rejected the Fancy Feast stuff and gobbled the baby food along with eating a little variety of the many dry foods we tried in an effort to find one that he really liked. While my facility does not treat cats with radioactive 131I, I have consulted with a veterinary medicine program at a nearby university that does perform these types of procedures to get myself in the "cat-patient" mode of thought. . I might even suggest using disposable gloves when handling the litter box duties and when caring for the cat during the isolation time. In almost all cases, your thyroid hormone levels will return to normal or below normal after radioactive iodine treatment. The goal of hyperthyroidism treatment is to lower the levels of thyroid hormones in the body. Hyperthyroidism in cats is a commonly diagnosed endocrinopathy with an overall prevalence of 2.4% in England which increases to 8.7% in cats aged 10 years or older. If you suspect your cat might be experiencing some of these symptoms, the next step is visiting your veterinarian for a blood test to check your cats thyroid hormone levels. Medication typically. Your cat can receive methimazole, a medication that inhibits thyroid hormone production. Risks unrelated to radioiodine therapy: In cats, an underactive thyroid is extremely rare. Thus, pate is a better choice for your cat than gravy food due to the latter's higher . Learn more about radioiodine therapy for hyperthyroidism, Learn about radioiodine therapy for thyroid carcinoma, Learn more aboutSamariumtherapy for primary or metastatic bone tumors. The radioactive iodine is useful in treating the condition that your veterinarian has diagnosed in your cat. About TheCatSite.com. Nearly all cats will be cured by a second treatment. Annual blood and urine tests are important in all cats seven years and older to detect hyperthyroidism before potentially irreversible damage occurs.
. 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. Copyright 2023 Leaf Group Ltd. / Leaf Group Media, All Rights Reserved. It is important to remember that old age is not a disease. 3. 5. Exposure limitations: Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. In cats > 95% of the radioiodine is excreted in the urine. These tests are needed to evaluate your cats overall health and predict the likelihood of complications with the chosen treatment protocol. Since fewer than 2% of cats with hyperthyroidism have cancerous growths of the thyroid gland, treatment is usually very successful. This may be particularly useful in cats with medical conditions that make other treatment options impossible. Tiki Cat Hanalei Luau Wild Salmon Wet Cat Food. As the thyroid levels return to normal, some cats may be able to adjust to their new diets quickly after treatment. Long-Term Health and Predictors of Survival for Hyperthyroid Cats Treated with Iodine 131. Committee on Environmental Health. Clinical Signs You'll have to give him this drug twice daily for the rest of his life, which treats but doesn't cure the condition. They may develop periodic vomiting or diarrhea, and fur may appear unkempt. Over time, this progresses to increased blood pressure, severe weight loss, heart disease, blindness, and kidney damage. Although it has a slightly higher iodine content than the previous option, Tiki Cat Hanalei Luau Wild Salmon is the best value for money. So excited we decided to go this route and cure her instead of just treating with daily medication. 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 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). The injection has no direct side effects. Amazingly despite over 35 years of veterinary experience treating hyperthyroid cats with radioiodine there are virtually no reported side effects. Researchers estimated a 12% increased risk for death from breast cancer and a 5% increased risk for death from .