Louisiana State University LSU Digital Commons There are four treatment options for feline hyperthyroidism: medication, radioactive iodine therapy, surgery, and dietary therapy. . The treatment you and your vet choose depends on several factors including how severe the disease is, your cats health, and what works best for your family. 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. Overall, weight gain was associated with development of hypothyroidism despite levothyroxine replacement . However, unless the retinal detachment is treated immediately, permanent blindness can occur. Thyroid scintigraphy may also be recommended to confirm a diagnosis and determine the size of the organ before surgery or radioactive iodine. Radioactive iodine therapy offers a cure through a simple injection that returns thyroid function to normal levels. I have a cat also and I know when she is happy and purring while sitting on my lap getting strokes, she drools. Montreal. . The anti-thyroid pill is methimazole, also known as Tapazole. Feline Hyperthyroidism - Cornell University College of Veterinary Medicine Studies show that weight gain is inevitable after radioiodine-induced hypothyroidism. Risks Associated with Radioiodine Therapy for Feline Hyperthyroidism - AVMI 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. Removal of the thyroid glands, called surgical thyroidectomy, is a relatively straightforward surgical procedure that has a good success rate. 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. Design and methods: Five hundred and four patients over 40 years of age with diffuse toxic goiter were treated with MMI for 18 months. Log in 24/7 to access your pets health care information. I-131 is normally a health concern after the . If methimazole dosing is discontinued, hyperthyroidism will return. 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. 122(6): p. 2444-61. of the radioactive iodine into your body because, just like the cat, any 131I intake you have will result in an uptake by your thyroid and in larger quantities could result in significant thyroid dose. Surgical patients may become hyperthyroid again if abnormal cells are missed during surgery or if new abnormal cells develop. However, it may not be appropriate for all cats (depending on other medical conditions) so important to work with your veterinarian and decide if using this therapeutic diet is the best way to manage your cats condition. These medications do not provide a cure for the disease, but they do allow either short-term or long-term control of hyperthyroidism. Researchers estimated a 12% increased risk for death from breast cancer and a 5% increased risk for death from . 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. Often, treating hyperthyroidism will unmask hidden kidney failure that will require additional care and is best detected early in the course of the disease. You may also be advised to suck on sour candy after treatment to help the radioactive iodine come out in your saliva. Of 247 patients receiving RAI for GD, 157 (79.6% female) had complete data and were included in the analysis. Natural background radiation exposure accounts for an average of 3.1 mSv/yr with variations depending on where you live. However, since wild-caught flaked Alaskan salmon is the first ingredient, it provides a lot of moisture. All bodily fluids in the cat will have trace amounts of radioactive material within them, but it will be most prevalent within the urine. Occasionally cats will act like they may have a sore throat for a couple of days after the radioiodine therapy. 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. Weight gain was similar for patients who received antithyroid drugs or radioiodine treatment but was significantly greater for patients who had been treated with thyroidectomy (5 kg vs 10 kg; P = 0.007). When choosing the best therapy for an individual cat, many factors must be considered. Treatment for hypothyroidism in cats is . The delivery of iodine is targeted to the overactive thyroid gland(s), the cat does not experience any radiation side effects at the normal therapy doses used to treat hyperthyroidism. If you can't bear to be away from him, or if he becomes very stressed or frightened when you're not around, that isolation could be difficult. These include weight loss, increased activity, and kitten like behaviour. This usually leads to permanent destruction of the thyroid, which will cure hyperthyroidism. It will take about a month for thyroid levels to return to normal in most cats. This is very important meaning that cats rarely develop an underactive thyroid gland (hypothyroidism) after radioiodine therapy. Of 135 patients with documented pubertal status . Other than unexplained weight loss, your cat may also become more restless, hyperactive, vocal, and extremely hungry! A treated cat has to remain hospitalized until its radiation level has fallen to within acceptable limits. But this generally resolves without intervention. Follow up blood work is essential to ensure kitty does not become hypothyroid which is too little thyroid. Weight change was analyzed in only 228 patients and 84% gained weight by 1 year after radioactive iodine therapy. Hypertension develops due to the increased pumping pressure and elevated heart rate that occurs with hyperthyroidism. 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. Slater M.R., Geller S. and Rogers K., Long-Term Health and Predictors of Survival for Hyperthyroid Cats Treated with Iodine 131. Pediatrics, 1998. Other therapeutic monitoring. Clinical Signs Thus, individuals who opt for . The radioactive isotope, Iodine-131 ( 131 I), is administered as a one-off injection. In some of these cats, blood pressure can become so high that retinal bleeding or retinal detachment will occur, resulting in sudden blindness. Exposure to high levels of dietary iodine may cause susceptible cats to develop hyperthyroidism. Hyperthyroidism | International Cat Care 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. 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. There are several treatment options, and your veterinarian will determine the best choice for your cat. In the US, the average person is exposed to an additional 3.0 mSv/yr from medical sources (predominantly CT scans). Secondary Problems The word "individuals" in this context means "people". This problem resolved rapidly after treatment. Some people also feel flushed. How long can a cat live after radioactive iodine treatment? However, because your cat will be radioactive for several days after receiving the shot, precautions must be taken during and after the treatment. Companion Animal Hospital in Ithaca, NY for cats, dogs, exotics, and wildlife, Equine and Nemo Farm Animal Hospitals in Ithaca, NY for horses and farm animals, Cornell Ruffian Equine Specialists, on Long Island for every horse, Ambulatory and Production Medicine for service on farms within 30 miles of Ithaca, NY, Animal Health Diagnostic Center New York State Veterinary Diagnostic Laboratory, Cornell University College of Veterinary Medicine Ithaca, New York 14853-6401. 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. 8. Since fewer than 2% of cats with hyperthyroidism have cancerous growths of the thyroid gland, treatment is usually very successful. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society. Some cats develop side effects from methimazole, such as vomiting, lethargy, anorexia, fever, liver damage, anemia, and a decrease in white blood cells. Medication typically. If left untreated and unmanaged, these changes may eventually compromise the normal function of the heart and can even lead to heart failure. Hyperthyroidism is a common disease in cats, and mostly afflicts cats middle-aged and older. What they are trying to prevent is the intake (ingestion, etc.) 1 Radioactive iodine (RAI)] is generally considered the optimal treatment for hyperthyroidism in cats. However, it may not be the best treatment for your particular cat. Risks from other illness. Radioactive iodine therapy. Managing Hyperthyroidism with Diet in Cats Radioactive iodine therapy is the treatment of choice, however, because it destroys abnormal thyroid tissue without damaging the surrounding tissue, providing a more permanent form of treatment. How does the risk from medical radiation compare to background radiation exposure? Let's tackle the external exposure first as it is the simplest concept. Medication and radioactive iodine therapy are just as effective at treating hyperthyroidism in cats as surgery and are less invasive, so surgical treatment is rarely chosen for treating this condition. Recurrence of the disease is a possibility in some cats. Miles K.G., Simpson S.A., Zimmerman R.B., et al. The majority of cats treated with radioactive iodine have normal hormone levels within one to two weeks of treatment. Symptoms include weight loss, muscle wasting, increased appetite, increased thirst and urination, vomiting, unkempt appearance, and sometimes hyperactivity. The good news is that virtually every client will already take steps to avoid this, even when radioactive iodine in their cat's urine is not the motivation. Risk of Ionizing Radiation Exposure to Children: A Subject Review. A radioactive cure for ailing older cats | Penn Today What may work for one cat may not work for another. But there are clear reasons for the precautions that the veterinarian has given you and I also recommend that you follow them. This disease is common in older cats. Dr. Heinze is an employee of Mark Morris Institute and has provided professional serviceshas done consulting for Lafeber and WellPet, given sponsored talks for Nestl Purina PetCare and the Pet Food Institute, and provided professional services to Balance IT.com and Mark Morris Institute. What To Expect After Radioactive Iodine Treatment Subscribe to always know when we add new material! In cats > 95% of the radioiodine is excreted in the urine. The advantages of radioactive iodine therapy are that the procedure most often cures hyperthyroidism, has no serious side effects, and does not require anesthesia. At the time of discharge, exposure levels measured at 6 feet from the patient are virtually indistinguishable from background levels. Feeding an iodine-limited diet (Hills Prescription Diet y/d) can resolve clinical signs and lower thyroid hormone concentration. Too cold? The radioiodine is eliminated in urine and feces. Radioactive Iodine (Radioiodine) Therapy for Thyroid Cancer This is because the parathyroid glands (responsible for calcium balance in the body) are near the thyroid gland and may be damaged or accidentally removed during surgery. A small number of cats will remain hyperthyroid after treatment, if this is the case your cat will need . After radioactive iodine treatment - Cancer Research UK Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. Further, the litter will be radioactive as most of the radioactive iodine will be excreted via this route. 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. Do not allow your cat to sleep against your body. 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. Hyperthyroid cats suffer overactive thyroid glands, circulating too much thyroid hormone through their system and affecting nearly every organ. Lack of appetite. Ultrasound of the heart (called echocardiography) may be recommended based on your cat's condition, especially if there is any concern about cardiomyopathy. Nera just had her 3 month checkup and her T4 level is down to 2.3! Diagnosis of feline hyperthyroidism is generally straightforward. Radioactive Iodine Therapy for Feline Hyperthyroidism This treatment is appropriate for cats with more surgical risk due to other health problems or who are exceptionally old. 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. What about radioactive iodine treatment for children and teenagers? Weight gain after RAI is typical. The medication can be given life-long or to stabilize the cat before other treatment. Radioactive iodine therapy is a very effective way to treat hyperthyroidism (I-131). If we restrict iodine, production of thyroxine decreases. Anti-thyroid drugs act by reducing the production and release of thyroid hormone from the thyroid gland. Employees of facilities that utilize radioactive materials may be categorized as "radiation workers" depending on their role. I might even suggest using disposable gloves when handling the litter box duties and when caring for the cat during the isolation time. Chance of significant, unhealthy weight gain is increased. If your cat requires daily medications for issues other than hyperthyroidism, he's not a candidate for radioactive iodine therapy. Feeding Hyperthyroid Cats Iodine restriction may help; weight loss is a . Change in BMI after radioactive iodine ablation for graves disease 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). 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. So, we must use distance and reduction of time near the source when dealing with patients and pets treated with 131I. 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. Will my cat gain weight after radioactive iodine treatment? How long can a cat live after radioactive iodine treatment? After treatment, the normal thyroid tissue will regain full function within 1-3 months. Unfortunately these cats may continue to deteriorate and may even die from their other non-thyroid diseases. . Putting on weight after thyroid radiation treatment | TheCatSite For this prescription diet to work, it must be the only food fed, which means no cheating with treats. She gained and ate a lot and we were more than happy. and Turrel J.M., A Multicompartmental Model for Iodide, Thyroxine, and Triiodothyronine Metabolism in Normal and Spontaneously Hyperthyroid Cats. Within one year after discontinuation of MMI, hyperthyroidism recurred in 104 patients. What to Feed a Cat With Hyperthyroidism? - Guide for Pet Owners So excited we decided to go this route and cure her instead of just treating with daily medication. . Because the thyroid needs iodine to produce hormones, the thyroid takes the radioiodine into the thyroid cells and the radiation destroys the overactive thyroid cells over time. The remainder is gone in about the next two months or so. Subscribe to always know when we add new material! You'll need to consider whether to have radioactive iodine (RAI) vs. other treatments for hyperthyroidism and Graves' disease (an immune system disorder that can cause hyperthyroidism). 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. This cat is showing weight loss and poor coat - typical signs of hyperthyroidism. Hyperthyroidism in cats - Veterinary Teaching Hospital 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. Radioactive Iodine Experience and Quarantine Times | Cat Forum 1 INTRODUCTION. What is happening in this procedure is that a portion of the radioactive iodine is being taken up by the cat's thyroid to treat its condition (hyperthyroidism, I assume?). It is also common for some cats to hide under the bed for a day or so after returning home as they de-stress following their out of home experience. Recurrence of hyperthyroidism is rare after I-131 therapy. Radioactive iodine (RAI) is a treatment method for hyperthyroidism and thyroid cancer. When the dose of radiation to the thyroid is very low, like might occur by accidental ingestion of litter box contents, then mutations leading to cancer can ensue. The good news is that there are many treatment options available to our hyperthyroid cats. Hyperthyroidism may also cause vomiting, diarrhea, and hyperactivity. under the skin, like a vaccine) and the radioactive iodine is quickly absorbed into the bloodstream.